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工业过程广义稳态的平均度量 被引量:1
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作者 罗旭光 万百五 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第3期198-202,共5页
针对工业过程广义稳态集合的度量问题进行了深入研究,证明了非线性系统在满足较宽的条件下,其稳态集合的中心名义值唯一存在。研究表明,该中心名义值作为工业过程广义稳态集合的平均度量是正确和恰当的。
关键词 工业过程 非线性系统 平均度量 混沌 广义稳态
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最大平均度量下的Bowen维数熵与测度下局部熵 被引量:1
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作者 孟如月 张瑞丰 《大学数学》 2021年第4期1-4,共4页
熵是反映动力系统复杂性的一个非常重要的量.本文研究了平均意义下的动力系统的性质,对于最大平均度量,引入了Bowen维数熵以及测度下局部熵的概念.并研究了它们之间的关系,说明了在最大平均度量下,Bowen维数熵依然可以由测度下局部熵估计.
关键词 最大平均度量 Bowen维数熵 测度下局部熵
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死端搅拌操作条件下平均膜污染度量指数变化
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作者 刘慧慧 王湛 《江西化工》 CAS 2024年第4期91-96,共6页
在死端搅拌微滤膜装置上,采用0.1μm孔径的PES平板微滤膜对酵母悬浮液进行过滤实验。研究瞬时膜污染度量指数(t)和平均膜污染度量指数■在不同操作条件下(搅拌速率、浓度、温度、压力和污染物)的变化规律。结果表明,搅拌速率200 rmp时(t... 在死端搅拌微滤膜装置上,采用0.1μm孔径的PES平板微滤膜对酵母悬浮液进行过滤实验。研究瞬时膜污染度量指数(t)和平均膜污染度量指数■在不同操作条件下(搅拌速率、浓度、温度、压力和污染物)的变化规律。结果表明,搅拌速率200 rmp时(t)最小,而■随搅拌速率的增加先增大后降低;在浓度、温度以及压力下,(t)均随时间递增,■随浓度递增。另外,■(酵母悬浮液)>■(活性污泥悬浮液)>■(高岭土悬浮液)则说明在实际过滤过程中,选择2 g/L、25℃和0.08 MPa作为固定操作条件,选择尽可能高搅拌速率和低料液浓度的高岭土悬浮液时的膜污染程度最轻。 展开更多
关键词 死端微滤 平均膜污染度量指数 操作条件
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p-平均对称差度量的Cauchy问题(Ⅰ) 被引量:1
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作者 李法朝 苏连青 仇计清 《河北科技大学学报》 CAS 1999年第4期5-10,共6页
从集合的对称差集合的Lebesgue 测度出发,建立了衡量Fuzzy 数之间差异的p-平均对称差度量dΔp ,讨论了(E,dΔp)中的Cauchy 序列的基本性质。
关键词 FUZZY数 平均对称差度量 Cauchy序列 集合 度量
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p-平均对称差度量的Cauchy问题(Ⅱ)
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作者 苏连青 李法朝 仇计清 《河北科技大学学报》 CAS 2000年第1期1-7,共7页
从集合的对称差集合的 L ebesgue测度出发 ,建立了衡量 Fuzzy数之间差异的p-平均对称差度量 dΔp,证明了 dΔp在空间 E1(K) ={ A~ |A~ ∈ E1,A0 K,K∈ I(R) }上是完备的拟度量 ,并举例说明 (E1,dΔ p)不是完备的拟度量空间。
关键词 FUZZY数 平均对称差度量 Cauchy序列 度量空间
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p-平均对称度量关于代数运算的收敛问题
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作者 李法朝 吴从炘 仇计清 《模糊系统与数学》 CSCD 2000年第2期53-59,共7页
引入了广义 Fuzzy数的概念 ,讨论了 p-平均对称差度量 dΔp (参见 [3])在广义 Fuzzy数空间 E* 上关于代数运算的收敛问题。
关键词 p-平均对称差度量 广义Fuzzy数 代数运算 收敛
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p-平均对称差度量的紧性刻画
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作者 李法朝 李丽霞 《河北师范大学学报(自然科学版)》 CAS 1999年第3期297-301,共5页
利用分析的方法结合台型模糊数的概念,证明了在模糊度量空间 E1 中,支集模糊一致有界的关于 p 平均对称差度量 d Δp 的闭集 U 为紧集的充分必要条件: U 关于 Lp 度量 Dp 为紧集。
关键词 FUZZY数 平均对称差度量 台型模糊数
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关于非负常曲率空间中度量平均的几个结果
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作者 杨世国 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第6期119-121,共3页
应用度量几何的理论与方法研究了非负常曲率空间中度量平均问题,建立了关于非负常曲率 空间中度量平均的几个几何不等式,作为其特例得到关于欧氏空间和球面空间中度量平均的一些重要 结果.
关键词 度量平均 单形 体积 外接球半径
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双曲空间中的度量平均和几个不等式
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作者 郑永爱 《扬州师院学报(自然科学版)》 CSCD 1993年第1期15-21,共7页
定义了双曲空间上的度量平均的概念,得到了关于度量平均的几个不等式。
关键词 双曲空间 度量平均 不等式
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球面型空间中单形单参数族按内二面角的度量平均
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作者 郭曙光 林波 《扬州师院学报(自然科学版)》 CSCD 1997年第2期11-17,共7页
引进了球面型空间中单形单参数族按内二面角度量平均的概念;讨论了按内二面角度量平均过程中单形的一些几何不变量的变化关系;给出了单形内二面角的一个不等式.
关键词 球面型空间 度量平均 单形 二面角 几何不等式
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度量平均与伪对称集
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作者 周加农 《西南民族学院学报(畜牧兽医版)》 1993年第2期136-138,共3页
给出了度量平均点集为—伪对称集的一类充分必要条件。
关键词 度量平均 伪对称集 度量平均点集
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双曲型空间中共球点集单参数族的度量平均
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作者 郭曙光 《湖南教育学院学报》 1997年第2期23-26,共4页
本文建立双曲型空间中共球点集单参数族的度量平均,讨论度量平均过程中点集覆盖半径之间的变化关系.并举例说明其应用.
关键词 双曲型空间 共球点集 度量平均 几何不等式
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p-对称差度量的收敛判别法及极限表达式
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作者 李法朝 李丽霞 蔡习宁 《河北师范大学学报(自然科学版)》 CAS 2000年第2期169-172,共4页
证明了支集一致有界的 Fuzzy数序列 {A~(n) }按 p -平均对称差度量 dΔp 收敛于 Fuzzy数 A~ 的充分必要条件是 :存在 h∈ [0 ,1] ,使得 {an(λ) }和 {bn(λ) }在 [0 ,h]上几乎处处收敛 ,且∫1h[m( A(n)λ ) ] pdλ→ 0 ( n→∞ ) (此... 证明了支集一致有界的 Fuzzy数序列 {A~(n) }按 p -平均对称差度量 dΔp 收敛于 Fuzzy数 A~ 的充分必要条件是 :存在 h∈ [0 ,1] ,使得 {an(λ) }和 {bn(λ) }在 [0 ,h]上几乎处处收敛 ,且∫1h[m( A(n)λ ) ] pdλ→ 0 ( n→∞ ) (此处 ,A(n)λ =[an(λ) ,bn(λ) ]表示 A~(n)的λ -截集 ) ;进而给出了 Fuzzy数序列按 dΔp 展开更多
关键词 p-平均对称差度量 收敛判别 极限表达式 模糊数
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非紧集上错误函数下自由半群作用的拓扑压
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作者 郭锴 肖倩 马东魁 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2022年第6期180-189,共10页
拓扑压是动力系统和遍历理论中的核心概念,它在热力学形式的研究中具有重要作用。随着物理过程的演化,演化过程在轨道计算中产生变化或误差是很自然的。然而,一个自适应系统应该随着时间的推移减少误差。本文利用C-P结构给出了错误函数... 拓扑压是动力系统和遍历理论中的核心概念,它在热力学形式的研究中具有重要作用。随着物理过程的演化,演化过程在轨道计算中产生变化或误差是很自然的。然而,一个自适应系统应该随着时间的推移减少误差。本文利用C-P结构给出了错误函数下自由半群作用的拓扑压的两个定义并证明它们是等价的,此外,还证明了非紧集上错误函数下自由半群作用的拓扑压和没有错误函数下自由半群作用的拓扑压是等价的。最后,应用上述定理举例证明了平均度量下的自由半群作用的拓扑压等价于Bowen度量下的自由半群作用的拓扑压。 展开更多
关键词 自由半群作用 拓扑压 错误函数 平均度量 C-P结构
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Asian climate change under 1.5-4 ℃ warming targets 被引量:12
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作者 XU Ying ZHOU Bo-Tao +3 位作者 WU Jie HAN Zhen-Yu ZHANG Yong-Xiang WU Jia 《Advances in Climate Change Research》 SCIE CSCD 2017年第2期99-107,共9页
Based on simulations of 18 CMIP5 models under three RCP scenarios, this article investigates changes in mean temperature and precipitation and their extremes over Asia in the context of global warming targets of 1.5-4... Based on simulations of 18 CMIP5 models under three RCP scenarios, this article investigates changes in mean temperature and precipitation and their extremes over Asia in the context of global warming targets of 1.5-4 ℃, and further compares the differences between 1.5 ℃ and 2 ℃ targets. Results show that relative to the pre-industrial era, the mean temperature over Asia increases by 2.3 ℃, 3.0 ℃, 4.6 ℃, and 6.0 ℃ at warming targets of 1.5 ℃, 2 ℃, 3 ℃, and 4 ℃, respectively, with stronger warming in high latitudes than in low latitudes. The corresponding enhancement in mean precipitation over the entire Asian region is 4.4%, 5.8%, 10.2%, and 13.0%, with significant regional differences. In addition, an increase in warm extremes, a decrease in cold extremes, and a strengthening in the variability of amounts of extreme precipitation are projected. Under the 1.5 ℃ target, compared with the climate under the 2 ℃ target, the mean temperature will be lower by 0.5-1 ℃ over Asia; the mean precipitation will be less by 5%-20% over most of Asia, but will be greater by about 10%-15% over West Asia and western South Asia; extreme high temperatures will be uniformly cooler throughout the Asian region, and the warming in extreme low temperatures will decrease significantly in high latitudes of Asia; extreme precipitation will be weaker over most of Asia but will be stronger over West Asia and western South Asia. Under the 1.5 ℃ and 2 ℃ warming targets, the probability of very hot weather (anomalies greater than 1σ, σ is standard deviation), extremely hot weather (anomalies greater than 3or), and extremely heavy precipitation (anomalies greater than 3σ) occurring will increase by at least once, 10%, and 10%, respectively, compared to the reference period (1861-1900). 展开更多
关键词 Global climate model CMIP5 Warming target Climate extreme Climate change
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Average Fidelity of Teleportation in Quantum Noise Channel 被引量:2
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作者 HAO Xiang ZHANG Rong ZHU Shi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期802-806,共5页
The effects of amplitude damping in quantum noise channels on average fidelity of quantum teleportation are analyzed in Bloeh sphere representation for every stage of teleportation. When the quantum channels are varie... The effects of amplitude damping in quantum noise channels on average fidelity of quantum teleportation are analyzed in Bloeh sphere representation for every stage of teleportation. When the quantum channels are varied from maximally entangled states to non-maximally entangled states, it is found that the effects of noise channels on the fidelity are nearly equivalent to each other for strong quantum noise. The degree of damage on the fidelity of non-maximally entangled channels is smaller than that of maximally entangled channels. The average fidelity of values larger than 2/3 may be one representation indirectly showing how much the unavoidable quantum noise is. 展开更多
关键词 average fidelity TELEPORTATION quantum noise channel Bloch sphere
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Flow Field Around Rushton Turbine in Stirred Tank by Particle Image Velocimetry Measurement 被引量:7
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作者 高殿荣 ACHARYA Sumanta +1 位作者 王益群 UHM Jongho 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第6期843-850,共8页
In this paper, particle image velocimetry (PIV) was used to measure the mean and root meansquare(RMS) velocity in the stirred tank with six-flat blade Rushton turbine and with no baffles. Two typesof motion patterns w... In this paper, particle image velocimetry (PIV) was used to measure the mean and root meansquare(RMS) velocity in the stirred tank with six-flat blade Rushton turbine and with no baffles. Two typesof motion patterns were studied. One was that the impeller runs at constant speed, the other was that the impellerruns at time-dependent speed and in a periodic way. The emphasis of the paper was on the comparison of meanand RMS velocity vector maps and profiles between these two types of motion patterns, and especial attention waspaid to the comparison of the mean velocity, time-averaged RMS velocity, phase averaged RMS velocity betweenthe constant 3 RPS (revolution per second) and time-dependent operation. The Reynolds number was between 763and 1527. The study explained the mechanism that time-dependent RPS is more efficient for mixing than that ofconstant RPS. 展开更多
关键词 particle image velocimetry mean velocity stirred tank root mean squarevelocity time-dependent speed
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Zonal Differences in Correlation Patterns Between Soil Organic Carbon and Climate Factors at Multi-extent 被引量:5
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作者 QIN Falyu SHI Xuezheng +2 位作者 XU Shengxiang YU Dongsheng WANG Dandan 《Chinese Geographical Science》 SCIE CSCD 2016年第5期670-678,共9页
Studying the relationship between climate factors and soil organic carbon (SOC) is vitally important. However, how SOC responses to climate (temperature and precipitation) at cohesive extents is poorly studied. Tw... Studying the relationship between climate factors and soil organic carbon (SOC) is vitally important. However, how SOC responses to climate (temperature and precipitation) at cohesive extents is poorly studied. Two transects of approximately the same length (transect P and transect T) were selected to examine the variation of SOC content in relation to mean annual temperature (MAT) and mean annual precipitation (MAP). The coefficients of partial correlation between SOC density and MAT (Rt) and MAP (Rp) were determined to quantify the relationships between SOC density and the two climate factors. The results indicated that for transect T, Rt was statistically significant once the extent level was greater than or equal to two fundamental extent units, while for transect P, Rp showed statistical significance only at extent levels which were greater than two fundamental extent traits. At the same extent levels but in different transects, Rts exhibited no zonal difference, but Rps did once the extent level was greater than two fundamental extent units. Therefore, to study the relationship between SOC density and different climate factors, different minimum extent levels should be ex- amined. The results of this paper could deepen the understanding of the impacts that SOC pool has on terrestrial ecosystem and global carbon cycling. 展开更多
关键词 soil organic carbon (SOC) mean annual temperature (MAT) mean annual precipitation (MAP) extent level coefficient of partial correlation
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Pathways of mesoscale variability in the South China Sea 被引量:5
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作者 庄伟 杜岩 +2 位作者 王东晓 谢强 谢尚平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期1055-1067,共13页
The propagation of oceanic mesoscale signals in the South China Sea(SCS) is mapped from satellite altimetric observations and an eddy-resolving global ocean model by using the maximum cross-correlation(MCC) method.Sig... The propagation of oceanic mesoscale signals in the South China Sea(SCS) is mapped from satellite altimetric observations and an eddy-resolving global ocean model by using the maximum cross-correlation(MCC) method.Significant mesoscale signals propagate along two major bands of high variability.The northern band is located west of the Luzon Strait,characterized by southwestward eddy propagation.Although eddies are the most active in winter,their southwestward migrations,steered by bathymetry,occur throughout the year.Advection by the mean flow plays a secondary role in modulating the propagating speed.The southern eddy band lies in the southwest part of the SCS deep basin and is oriented in an approximately meridional direction.Mesoscale variability propagates southward along the band in autumn.This southward eddy pathway could not be explained by mean flow advection and is likely related to eddy detachments from the western boundary current due to nonlinear effects.Our mapping of eddy propagation velocities provides important information for further understanding eddy dynamics in the SCS. 展开更多
关键词 sea level mesoscale variability maximum cross-correlation South China Sea (SCS)
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Simulation of Climate Change Scenarios for Phu Luong Watershed in Northern Viet Nam 被引量:1
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作者 Phan Dinh Binh 《Journal of Environmental Science and Engineering(B)》 2012年第11期1263-1270,共8页
The purpose of this paper is to apply "LARS-WG (Long Ashton Research Station--Weather Generator)" model to simulate the climate change scenarios for Phu Luong watershed in northem Viet Nam. Results indicated that ... The purpose of this paper is to apply "LARS-WG (Long Ashton Research Station--Weather Generator)" model to simulate the climate change scenarios for Phu Luong watershed in northem Viet Nam. Results indicated that LARS-WG adequately predicted precipitation and temperature with R2 = 0.80 and 0.73, respectively. Likewise, p-value of F test = 0.062 and p-value of t test = 0.885 for precipitation, meanwhile, for temperature are 0.092 and 0.564 at 0.05 level of significance, respectively. Moreover, results also stated that mean annual precipitation increases 1.62%, 2.17% and 3.96% and mean annual temperature increases 0.6 ℃, 0.8 ℃ and 1.05 ℃ in 2020, 2030 and 2040, respectively, with respect to those from baseline periods. This study also showed that LARS-WG model was used successfully for Viet Nam's watershed conditions. 展开更多
关键词 LARS-WG climate change precipitation simulation watershed.
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