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推广的Grunwald插值在L_(M,ω)^(Ba)空间中的逼近 被引量:2
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作者 刘小妍 吴嘎日迪 《数学杂志》 CSCD 北大核心 2011年第5期869-874,共6页
本文研究了推广的Grunwald插值算子在L_(M,ω)^(Ba)空间中的逼近.利用Orlicz空间范数和L_(M,ω)^(Ba)空间范数关系的不等式,以第一类Chebyshev多项式的零点为结点时,获得了两类推广的Grunwald插值算子在加权的L_(M,ω)^(Ba)空间中的逼近阶.
关键词 Grunwald插值 l_(m ω)^(Ba)空间 逼近阶
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On the existence and stability of traversable wormhole solutions with novel shapefunctions in the framework of F(R,L_(m))gravity
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作者 Sourav Chaudhary Jitendra Kumar +2 位作者 S K Maurya Sweeti Kiroriwal Abdul Aziz 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第5期114-127,共14页
In this work,we have explored wormhole(WH)solutions in F(R,L_(m))gravity by assuming the Morris-Thorne WH metric and F(R,Lm)=R/2+(1+γR)L_(m),whereγis the free model parameter.We determined the WH solutions by utiliz... In this work,we have explored wormhole(WH)solutions in F(R,L_(m))gravity by assuming the Morris-Thorne WH metric and F(R,Lm)=R/2+(1+γR)L_(m),whereγis the free model parameter.We determined the WH solutions by utilizing two newly developed shape functions(SF)that satisfy all basic conditions for a WH’s physical validity.We also observe that the null energy condition(NEC)behaves negatively.Finally,for both models,we use the volume integral quantifier(VIQ)and Tolman-Oppenheimer-Volkoff(TOV)equation to determine how much exotic matter is needed near the WH throat and the stability of the WH.The extensive detailed discussions of the matter components have been done via graphical analysis.The obtained WH geometries meet the physically acceptable conditions for a stable wormhole. 展开更多
关键词 energy conditions WORmHOlE exotic matter F(R l_(m))gravity
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Wormhole solutions under the effect of dark matter in f(R,L_(m))gravity
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作者 Lakhan V Jaybhaye Moreshwar Tayde PK Sahoo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第5期102-113,共12页
In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo regions.The current study aims t... In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo regions.The current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,L_(m))gravity models.According to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free parameters.In addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape function.Further,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo. 展开更多
关键词 f(R l_(m))gravity WORmHOlE dark matter(Some figures may appear in colour only in the online journal)
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Analytical study on abnormal change in time-variable gravity at Yichang seismostation before the M5.1 Badong earthquake 被引量:4
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作者 Wei Jin Shen Chongyang +1 位作者 Liu Shaoming Dai Miao 《Geodesy and Geodynamics》 2014年第1期55-63,共9页
An M5.1 earthquake occurred in Badong County, only 66 km from the Three Gorges Dam, on De- cember 16, 2013. The continuous gravity observation data obtained at Yichang seismostation nearest to the epi- center (96 km... An M5.1 earthquake occurred in Badong County, only 66 km from the Three Gorges Dam, on De- cember 16, 2013. The continuous gravity observation data obtained at Yichang seismostation nearest to the epi- center (96 km) were analyzed, and it was found that the continuous gravity observation data obtained in this rainy season did not exhibit a characteristic of seasonal change in gravity identical to that in the past years, and thereafter the M5.1 Badong earthquake occurred. Numerical simulation revealed that the water storage and discharge of the Three Gorges reservoir generated seasonal change in gravity, and the changes in atmospheric pressure and gravity load were not the main sources of the seasonal change of continuous gravity observation data whether in respect of magnitude or phase and did not have obvious breaking change on annual variation before the earthquake. Through analysis of the seasonal change data observed on the same site including cavern temperature, rainfall data and global terrestrial water model (CPC) simulated water load, it was thought that, in the observation room with cavern temperature change of only -0.1 l^C/a at Yichang seismostation, the sea- sonal change of continuous gravity observation result mainly originated from the seasonal change in rainfall. In the case that the changes in rainfall and its water load did not have evident breaking change on annual varia- tion law before the earthquake, if the MS. 1 Badong earthquake was the cause of the breaking change on annual variation law in Yichang this time, then it was believed through analysis of crust expansion ratio that similar a- nomaly should occur at a crust expansion and compression intersection, no more than 100 km away from the epicenter. 展开更多
关键词 continuous gravity observation water storage of the Three Gorges reservoir m5.1 Badong earth-quake
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Gravity anomaly before the Leshan M5.0 earthquake? 被引量:1
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作者 Wei Jin Liu Ziwei +3 位作者 Sun Shaoan Kang Kaixuan Shen Chongyang Li Hui 《Geodesy and Geodynamics》 2015年第2期101-105,共5页
The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations ... The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations one month before the Leshan M5.0 earthquake. 展开更多
关键词 gravity gradient Continuous gravity observations Nonlinear gravity change leshan m5.0 earthquake mobile gravity observation network Accumulation gravity change Different gravity change North-South Seismic Belt
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Variation of gravity before the Alxa Zuoqi M5.8 earthquake 被引量:1
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作者 Jianlin Feng Jin Wei +3 位作者 Yujuan Tan Jianzeng Qin Bangwu Huang Ruyi Xie 《Geodesy and Geodynamics》 2016年第4期295-301,共7页
In this study, a classic survey adjustment computation method was used for data obtained in the Inner Mongolia and Ningxia gravimetric networks between September 2013 and April 2015 so as to investigate the variation ... In this study, a classic survey adjustment computation method was used for data obtained in the Inner Mongolia and Ningxia gravimetric networks between September 2013 and April 2015 so as to investigate the variation of gravity before the Alxa Zuoqi M5.8 earthquake. The relationship between gravity variation and the Alxa Zuoqi M5.8 earthquake was analyzed. The results showed that: (1) the severe variation in gravity field at the test sites before the Alxa Zuoqi M5.8 earthquake, as well as the subsequent accelerated rising, might be an earthquake precursor; (2) the Alxa Zuoqi M5.8 earthquake occurred at the turning point where the high-gravity gradient zone changed from the NE direction to NW. 展开更多
关键词 Repeated gravimetry gravity variations Alxa Zuoqi m5.8 earthquake High gravity gradient belt
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Einstein’s General Relativity and Pure Gravity in a Cosserat and De Sitter-Witten Spacetime Setting as the Explanation of Dark Energy and Cosmic Accelerated Expansion
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第2期332-339,共8页
Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 k... Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 killing vector fields corresponding to Witten’s five Branes model in eleven dimensional M-theory we reason that 504 of the 528 are essentially the components of the relevant killing-Yano tensor. In turn this tensor is related to hidden symmetries and torsional coupled stresses of the Cosserat micro-polar space as well as the Einstein-Cartan connection. Proceeding in this way the dark energy density is found to be that of Einstein’s maximal energy mc2 where m is the mass and c is the speed of light multiplied with a Lorentz factor equal to the ratio of the 504 killing-Yano tensor and the 528 states maximally symmetric space. Thus we have E (dark) = mc2 (504/528) = mc2 (21/22) which is about 95.5% of the total maximal energy density in astounding agreement with COBE, WMAP and Planck cosmological measurements as well as the type 1a supernova analysis. Finally theory and results are validated via a related theory based on the degrees of freedom of pure gravity, the theory of nonlocal elasticity as well as ‘t Hooft-Veltman renormalization method. 展开更多
关键词 General RElATIVITY COSSERAT micro-Polar Space Dark Energy Teleparellelism Witten’s m-THEORY De Sitter SPACETImE Killing-Yano Tensor Einstein-Cartan RElATIVITY PURE gravity Kaluza-Klein Theory Nonlocal Elasticity 't Hooft-Veltman Renormalization
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基于Pro/M的大口径反射镜的变形分析及其支撑优化 被引量:6
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作者 陈晓娟 傅学农 +3 位作者 吴文凯 徐元利 王美聪 钟继根 《机械设计》 CSCD 北大核心 2008年第2期68-70,共3页
针对某大型激光装置中使用数量众多的大口径反射镜结构,运用Pro/E软件中的Mechanica研究其受重力影响的变形,并对反射镜的支撑结构参数进行灵敏度分析和优化计算,寻找使得反射镜片变形最小的结构参数,为大口径反射镜组件结构的设计提供... 针对某大型激光装置中使用数量众多的大口径反射镜结构,运用Pro/E软件中的Mechanica研究其受重力影响的变形,并对反射镜的支撑结构参数进行灵敏度分析和优化计算,寻找使得反射镜片变形最小的结构参数,为大口径反射镜组件结构的设计提供依据。 展开更多
关键词 Pro/m 大口径反射镜 重力变形 优化
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M船型阻力模型试验研究 被引量:10
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作者 唐建飞 黄武刚 《中国舰船研究》 2014年第5期49-52,共4页
为准确评估M船型的水动力特性,掌握该船型的阻力特性和船型特征,对该船型进行阻力模型试验研究。通过测定不同排水量、不同重心纵向位置下船模的阻力值、纵倾角及重心升沉值,研究排水量和重心纵向位置对该船型阻力性能的影响。试验结果... 为准确评估M船型的水动力特性,掌握该船型的阻力特性和船型特征,对该船型进行阻力模型试验研究。通过测定不同排水量、不同重心纵向位置下船模的阻力值、纵倾角及重心升沉值,研究排水量和重心纵向位置对该船型阻力性能的影响。试验结果表明:M船型具有与常规滑行艇不一样的阻力特性,该船型拥有2个高速阻力峰,当航速持续增大越过第1个高速阻力峰后,阻力值有明显的回落,当航速继续增大越过第2个高速阻力峰后,阻力值基本保持不变,且2个高速阻力峰出现的航速与排水量大小和重心纵向位置的相关性不大。 展开更多
关键词 m船型 阻力 模型试验 排水量 重心纵向位置 阻力峰
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甘东南重力、b值异常与岷县—漳县M6.6地震关系探讨 被引量:2
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作者 冯建林 李德庆 +3 位作者 檀玉娟 秦建增 谢汝一 刘冬阳 《地震工程学报》 CSCD 北大核心 2018年第4期802-807,共6页
利用甘东南测网2010—2014年的流动重力观测数据,分析2013年7月22日甘肃岷县—漳县M6.6地震前后1a尺度的重力场变化,并结合地震b值图像和GNSS结果进一步分析甘东南重力、b值异常与岷县—漳县M6.6地震的关系,结果表明:(1)测区重力异常经... 利用甘东南测网2010—2014年的流动重力观测数据,分析2013年7月22日甘肃岷县—漳县M6.6地震前后1a尺度的重力场变化,并结合地震b值图像和GNSS结果进一步分析甘东南重力、b值异常与岷县—漳县M6.6地震的关系,结果表明:(1)测区重力异常经历了由"区域重力负值变化→持续负值变化→转折上升正变化—发震→震后恢复变化"的时空演化过程;(2)岷县—漳县M6.6地震前后b值曲线出现"低值—高值—回落发震"的变化特征;(3)岷县—漳县M6.6地震发生在重力变化高梯度带上、"0"等值线附近和低b值区域。 展开更多
关键词 重力异常 b值异常 岷县-漳县m6.6地震 甘东南
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2020年1月19日新疆伽师MS6.4地震前重力场变化特征研究 被引量:4
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作者 李瑞 杨磊 +3 位作者 赵磊 丁宇 孙小旭 陈丽 《内陆地震》 2020年第1期95-102,共8页
针对新疆伽师M S6.4地震,利用多期重复流动重力观测数据并结合地震地质资料分析和研究此次地震前重力异常变化特征。研究结果表明:此次地震发生在最新观测的半年尺度零值线附近,两年累计变化量达到-100×10-8 m·s-2,2018年4月... 针对新疆伽师M S6.4地震,利用多期重复流动重力观测数据并结合地震地质资料分析和研究此次地震前重力异常变化特征。研究结果表明:此次地震发生在最新观测的半年尺度零值线附近,两年累计变化量达到-100×10-8 m·s-2,2018年4月观测的半年尺度重力场变化形成了以巴楚—阿图什为长半轴的椭圆形重力异常低值异常区,长半轴与柯坪断裂带走向一致。 展开更多
关键词 伽师mS6.4地震 流动重力 前兆异常 零值线
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2014年康定M_S6.3级地震前后的重力变化特征 被引量:3
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作者 郑兵 杨洋 +6 位作者 马伶俐 易天阳 李菲菲 廖明辉 温军军 王伟力 高丽君 《四川地震》 2019年第3期18-23,共6页
利用四川地区2010年8月至2015年3月的流动重力观测数据作出重力场等值线变化图像,研究分析2014年康定MS6.3级地震前后的重力变化特征,结果表明:(1)三岔口地区长期保持区域性重力正值变化异常及重力变化高梯度带;(2)在康定MS6.3级地震前... 利用四川地区2010年8月至2015年3月的流动重力观测数据作出重力场等值线变化图像,研究分析2014年康定MS6.3级地震前后的重力变化特征,结果表明:(1)三岔口地区长期保持区域性重力正值变化异常及重力变化高梯度带;(2)在康定MS6.3级地震前后三岔口地区的区域性重力正值变化异常及重力变化高梯度带变化并不是特别显著;(3)在康定MS6.3级地震前震区重力变化等值线出现四象限区域或者类似于四象限区域的分布特征;(4)康定MS6.3级地震发震位置处于0值线附近且0值线在此处发生明显的转折、畸变;(5)康定MS6.3级地震发生在重力减小后回调增加的过程中,震后重力继续回调增加。 展开更多
关键词 流动重力观测数据 康定mS6.3级地震 重力变化特征
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岷县-漳县M_S6.6地震前重力分形指数异常分析
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作者 许康生 李英 张卫东 《大地测量与地球动力学》 CSCD 北大核心 2019年第7期743-746,共4页
以2013-07-22甘肃岷县与漳县交界的MS6.6地震为研究对象,采用去趋势波动分析方法处理兰州、高台2个台2011~2015年重力观测资料,试图提取这次地震前的相关重力异常信息。结果表明,以9.4倍的该台分形指数标准差为异常阈值,岷县-漳县地震前... 以2013-07-22甘肃岷县与漳县交界的MS6.6地震为研究对象,采用去趋势波动分析方法处理兰州、高台2个台2011~2015年重力观测资料,试图提取这次地震前的相关重力异常信息。结果表明,以9.4倍的该台分形指数标准差为异常阈值,岷县-漳县地震前这2个台的重力分形指数均出现相似的异常升高过程,表明震前重力变化具有定向持续特征,显示出长程相关性,是孕震过程中物质运移、密度连续变化的反映,应该是与这次地震有关联的重要信息。结合其他学者的研究结果初步推测,这个异常变化可能与中下地壳乃至上地幔的物质运移有关。 展开更多
关键词 重力 去趋势波动分析 分形指数 岷县-漳县mS6.6地震
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21世纪基本物理学(M理论)及其哲学思考
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作者 薛晓舟 《河南教育学院学报(自然科学版)》 2000年第1期17-21,共5页
本文在于探索M理论的哲学问题。全文分三个部分。第一 ,2 0世纪基本物理学的成就和问题 ;第二 ,M理论的重要概念 ;第三 。
关键词 量子引力 超弦 m理论 哲学 基本物理学 超块 时空11维 对偶性 21世纪
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利用小波变换研究民乐M6.1地震前区域重力场变化特征
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作者 宁亚灵 吕海杰 +2 位作者 程紫燕 王翾潞 韩磊 《地震地磁观测与研究》 2015年第5期15-20,共6页
对民乐M 6.1地震前4年河西地区重力场变化进行小波分解,结果表明:重力异常变化一阶小波分体呈现随机性与局部性,反映浅层和局部质量变化引起重力变化;二阶小波分解与地质结构一致,反映断层活动引起的重力变化;三阶小波分解结果表明,在民... 对民乐M 6.1地震前4年河西地区重力场变化进行小波分解,结果表明:重力异常变化一阶小波分体呈现随机性与局部性,反映浅层和局部质量变化引起重力变化;二阶小波分解与地质结构一致,反映断层活动引起的重力变化;三阶小波分解结果表明,在民乐M 6.1地震前,重力显著改变,显示深部物质状态发生变化是引起此次地震发生的重要因素;四阶小波分解反映深部物质状态引起重力变化,对此次民乐M 6.1地震反应不明显。地震发生后,震区构造活动减弱,各阶小波分解对地震反应不明显。 展开更多
关键词 河西地区 重力场 小波分解 民乐m 6.1地震
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基于0.2 m高分辨率测井系列的表外薄差水淹层解释新技术 被引量:8
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作者 董建刚 苗清 刘江 《大庆石油地质与开发》 CAS CSCD 北大核心 2017年第2期123-128,共6页
针对高含水油田测井分辨率不足的实际和表外储层有效解释方法的缺失,充分利用0.2 m高分辨率测井新系列独特的技术优势,准确求取薄差层地层水电阻率、含水饱和度、驱油效率等地质参数。在此基础上,通过水淹状态敏感参数的优选,成功建立... 针对高含水油田测井分辨率不足的实际和表外储层有效解释方法的缺失,充分利用0.2 m高分辨率测井新系列独特的技术优势,准确求取薄差层地层水电阻率、含水饱和度、驱油效率等地质参数。在此基础上,通过水淹状态敏感参数的优选,成功建立起水淹状态方程和重心法相结合的水淹判别方法,既准确判断出遵循"四性关系"的储层水淹级别,又解决了特征参数正态性带来的矛盾,建立起表外薄差层解释新方法,填补了表外薄差层有效解释方法这一空白,形成与新测井技术相配套的水淹层解释新技术。通过4口取心井资料验证,薄差层解释符合率高达87.5%,为特高含水期油田持续稳产提供了有力技术支撑。 展开更多
关键词 0.2 m分辨率 地层水电阻率 状态方程 重心判别方法 薄差水淹层
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M理论及其哲学意义 被引量:3
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作者 冯宇 薛晓舟 《自然辩证法研究》 CSSCI 北大核心 2000年第5期1-5,17,共6页
M理论是 2 1世纪基本物理学研究的重要前沿阵地。本文从M理论的基本内容出发 ,阐述其带来的一些自然哲学问题。
关键词 量子引力 m理论 哲学 量子力学 狭义相对论
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重磁方法在金川铜镍矿东延M-15异常勘查中的应用 被引量:7
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作者 张翔 赵晓平 谢志峰 《物探与化探》 CAS CSCD 北大核心 2010年第2期139-143,共5页
M-15磁异常(东湾异常)是国内外学者关注的寻找铜镍矿的重点预测区之一。该异常处于全覆盖区,前人推断它是由超基性岩体引起的。本次采用重、磁方法和已知白家咀子超基性岩体磁异常特征对比,认为M-15系非同源重磁异常,以磁力高、重力低... M-15磁异常(东湾异常)是国内外学者关注的寻找铜镍矿的重点预测区之一。该异常处于全覆盖区,前人推断它是由超基性岩体引起的。本次采用重、磁方法和已知白家咀子超基性岩体磁异常特征对比,认为M-15系非同源重磁异常,以磁力高、重力低为组合特征,异常体埋深较大,磁异常可能为1200 m以下的超基性岩引起,重力低异常系埋深1 000 m左右的龙首山群元古界基地凹陷引起。这一结论对于扩大铜镍矿源起到了积极的作用。 展开更多
关键词 m-15磁异常 重力测量 磁法测量 重磁异常反演 铜镍矿
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3GDMC1000/720AI无压三产品重介质旋流器在永龙选煤厂的应用 被引量:3
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作者 徐州 《选煤技术》 CAS 2018年第3期60-62,共3页
为了解决永龙选煤厂中煤带精煤量偏高的问题,结合3GDMC1000/720AI无压三产品重介质旋流器的技术特征,对问题原因进行分析,并采取了一系列改进措施。生产实践表明:中煤带精煤量下降10.56个百分点,洗选精煤产率提高0.20个百分点,每年可多... 为了解决永龙选煤厂中煤带精煤量偏高的问题,结合3GDMC1000/720AI无压三产品重介质旋流器的技术特征,对问题原因进行分析,并采取了一系列改进措施。生产实践表明:中煤带精煤量下降10.56个百分点,洗选精煤产率提高0.20个百分点,每年可多回收精煤2 400 t。 展开更多
关键词 无压三产品重介质旋流器 中煤带精煤量 矸石带中煤量 精煤产率
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Nash Embedding of Witten’s M-Theory and the Hawking-Hartle Quantum Wave of Dark Energy 被引量:2
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2013年第10期1417-1428,共12页
Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anythin... Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anything resembling ordinary physical energy density. It is shown here using Nash embedding that the ratio of “solid” M-theory spacetime to its required embedding “non-spacetime” is 1/22 for a classical theory and 1/22.18033989 for an analogous fractal theory. This then leads to a maximal ordinary energy density equation equal to that of Einstein’s famous formula E=mc2 but multiplied with in full agreement with previous results obtained using relatively more conventional methods including running the electromagnetic fine structure constant in the exact solution of the hydrogen atom. Consequently, the new equation corresponds to a quantum relativity theory which unlike Einstein’s original equation gives quantitative predictions which agree perfectly with the cosmological measurements of WMAP and the analysis of certain supernova events. Never the less in our view dark energy also exists being the energy of the quantum wave amounting to 95.5 present of the total Einstein theoretical energy which is blind to any distinction between ordinary energy of the quantum particle and the dark energy of the quantum wave. However, since measurement leads to the collapse of the Hawking-Hartle quantum wave, dark energy being a quantum wave non-ordinary energy could not possibly be measured in the usual way unless highly refined quantum wave non-demolition technology is developed if possible. It is a further reason that dark energy having a different sign to ordinary energy is the cause behind the anti gravity force which is pushing the universe apart and accelerating cosmic expansion. Consequently it can be seen as the result of anticlastic Cartan-like curvature caused by extra compactified dimensions of spacetime. A simple toy model demonstration of the effect of curvature in a “material” space is briefly discussed. 展开更多
关键词 NASH Euclidean EmBEDDING QUANTUm Entanglement Dark ENERGY of the QUANTUm WAVE QUANTUm gravity Ordinary ENERGY of the QUANTUm Particle Hawking-Hartle WAVE of the Cosmos QUANTUm WAVE Non-Demolition Witten’s m-THEORY
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