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基于真实报道理念的记者采访数理性思维分析 被引量:1
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作者 刘大泳 《新闻传播》 2013年第3期87-87,共1页
记者的新闻采访过程其实就是对事实本质的涵义进行认识和分析的过程。记者要想写出能吸引读者注意并且有价值的新闻就必须对新闻事实进行横向或者纵向的截取与剖析。如何抓住事实报道的落脚点,从而把握住事实的本质是每一个新闻工作者... 记者的新闻采访过程其实就是对事实本质的涵义进行认识和分析的过程。记者要想写出能吸引读者注意并且有价值的新闻就必须对新闻事实进行横向或者纵向的截取与剖析。如何抓住事实报道的落脚点,从而把握住事实的本质是每一个新闻工作者都应思考的问题。文中就新闻报道中如何使用数理性思维来构建真实报道提出了自己的看法。 展开更多
关键词 真实报道 记者 数理性思维
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抽样调查的数理性及辩证性
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作者 郑瑛 《青海统计》 2002年第1期28-29,共2页
随着经济形势的发展变化,统计工作使用抽样调查方法已成为统计工作领域的一项重要内容。抽样调查是一种非全面调查,它包括样本调查和推断总体两个方面。这种方法就是在研究某一总体的综合指标时,不去研究总体的所有各个单位,而是根据科... 随着经济形势的发展变化,统计工作使用抽样调查方法已成为统计工作领域的一项重要内容。抽样调查是一种非全面调查,它包括样本调查和推断总体两个方面。这种方法就是在研究某一总体的综合指标时,不去研究总体的所有各个单位,而是根据科学的统计只从总体中按照随机的原则抽取一部分样本来进行实际调查,然后运用数理统计的原理以抽样总体的数量特征来推断全及总体的数量特征。抽样调查是观察和研究大量随机现象的调查。实践证明,观察和研究了大量的同一随机现象后,通常总能揭露出一种完全确定的规律性。 展开更多
关键词 抽样调查 统计调查 数理性 辩证性 抽样误差
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小学低年级数学理性思维现状调查分析——以重庆市南岸区珊瑚实验小学为例
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作者 匡永锋 《进展》 2020年第14期141-143,共3页
理性思维是学习数学所不可或缺的一种思维能力。针对小学低年级理性思维培养的现状进行调查研究,意在探究培养小学生理性思维的所存在的问题与解决方案,为培养小学生良好的科学认知与求真务实的精神打下基础。本次问卷调查为探究培养小... 理性思维是学习数学所不可或缺的一种思维能力。针对小学低年级理性思维培养的现状进行调查研究,意在探究培养小学生理性思维的所存在的问题与解决方案,为培养小学生良好的科学认知与求真务实的精神打下基础。本次问卷调查为探究培养小学生理性思维所进行的研究提供了基础依据。 展开更多
关键词 小学低年级理性思维 调查分析
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构成教学研究 被引量:3
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作者 袁涛 《昆明大学学报》 2004年第2期67-71,共5页
在“艺术与技术的统一”的口号下 ,包豪斯 (Bauhaus)的艺术家们一反当时的传统和做法 ,潜心研究新的造形方法和设计理念。构成就是在这种背景下 ,脱离了对具体内容的表现 ,从美术的教学中脱胎、演变、产生和发展的。虽然构成与美术之间... 在“艺术与技术的统一”的口号下 ,包豪斯 (Bauhaus)的艺术家们一反当时的传统和做法 ,潜心研究新的造形方法和设计理念。构成就是在这种背景下 ,脱离了对具体内容的表现 ,从美术的教学中脱胎、演变、产生和发展的。虽然构成与美术之间存在着关联 ,但它们各自研究的重点各异 ,方法不同。所以在构成的教学过程中 ,必须遵循构成本身的特点 ,突出构成的属性和重点。 展开更多
关键词 构成课程 教学研究 艺术设计 数理性 逻辑性 纯形态 几何形态
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First-principle calculations of ductile CeAg intermetallic compound 被引量:1
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作者 史耀君 杜宇雷 陈光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期654-660,共7页
The first-principle calculations were performed to investigate the structural,mechanical,electronic and thermal properties of the binary ductile intermetallic compound CeAg with B2(CsCl) structure.The calculated val... The first-principle calculations were performed to investigate the structural,mechanical,electronic and thermal properties of the binary ductile intermetallic compound CeAg with B2(CsCl) structure.The calculated value of lattice constant a0 for CeAg with generalized gradient approximation is 3.713-,which is in better agreement with experimental data than local spin density approximation.The negative energy of formation implies that CeAg with B2 structure is thermodynamically stable phase.The greater separation between the d bands of Ce and Ag results in weaker bond hybridization of Ce d—Ag d,which prevents formation of directional covalent bonding.The three independent elastic constants(C11,C12 and C44) are derived and the bulk modulus,shear modulus,elastic modulus,anisotropy factor,and Poisson ratio are determined to be 57.6 GPa,15.8 GPa,43.4 GPa,3.15 and 0.374,respectively.The elastic constants meet all the mechanical stability criteria.The value of Pugh's criterion is 3.65.The ductility of CeAg is predicted if Pugh's criterion is greater than 1.75.Furthermore,the variations of volume,bulk modulus,heat capacity,and thermal expansion coefficient with temperature and/or pressure were calculated and discussed. 展开更多
关键词 CeAg FIRST-PRINCIPLE elastic constant thermodynamic property
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Characteristics of Phytoplankton and Its Correlation with Water Environment in SFTWs 被引量:1
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作者 张丹 吴小慧 +4 位作者 黄民生 何岩 张勇 童敏 潘震 《Agricultural Science & Technology》 CAS 2011年第3期439-442,共4页
[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,ph... [Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration. 展开更多
关键词 SFTWs PHYTOPLANKTON Community structure Diversity index Physicochemical indexes
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Simultaneous inversion of petrophysical parameters based on geostatistical a priori information 被引量:11
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作者 印兴耀 孙瑞莹 +1 位作者 王保丽 张广智 《Applied Geophysics》 SCIE CSCD 2014年第3期311-320,351,共11页
The high-resolution nonlinear simultaneous inversion of petrophysical parameters is based on Bayesian statistics and combines petrophysics with geostatistical a priori information. We used the fast Fourier transform–... The high-resolution nonlinear simultaneous inversion of petrophysical parameters is based on Bayesian statistics and combines petrophysics with geostatistical a priori information. We used the fast Fourier transform–moving average(FFT–MA) and gradual deformation method(GDM) to obtain a reasonable variogram by using structural analysis and geostatistical a priori information of petrophysical parameters. Subsequently, we constructed the likelihood function according to the statistical petrophysical model. Finally, we used the Metropolis algorithm to sample the posteriori probability density and complete the inversion of the petrophysical parameters. We used the proposed method to process data from an oil fi eld in China and found good match between inversion and real data with high-resolution. In addition, the direct inversion of petrophysical parameters avoids the error accumulation and decreases the uncertainty, and increases the computational effi ciency. 展开更多
关键词 Geostatistical a priori information PETROPHYSICS Bayesian statistics simultaneous inversion
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Anisotropy rock physics model for the Longmaxi shale gas reservoir,Sichuan Basin,China 被引量:9
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作者 刘喜武 郭智奇 +1 位作者 刘财 刘宇巍 《Applied Geophysics》 SCIE CSCD 2017年第1期21-30,188,共11页
The preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. We introduce the clay lamination (CL) parameter to the Backus averaging method to describe the intrinsic shale anisotropy induc... The preferred orientation of clay minerals dominates the intrinsic anisotropy of shale. We introduce the clay lamination (CL) parameter to the Backus averaging method to describe the intrinsic shale anisotropy induced by the alignment of clay minerals. Then, we perform the inversion of CL and the Thomsen anisotropy parameters. The direct measurement of anisotropy is difficult because of the inability to measure the acoustic velocity in the vertical direction in boreholes and instrument limitations. By introducing the parameter CL, the inversion method provides reasonable estimates of the elastic anisotropy in the Longmaxi shale. The clay content is weakly correlated with the CL parameter. Moreover, the parameter CL is abnormally high at the bottom of the Longmaxi and Wufeng Formations, which are the target reservoirs. Finally, we construct rock physics templates to interpret well logging and reservoir properties. 展开更多
关键词 Longmaxi SHALE ANISOTROPY rock physics clay lamination
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论风险与企业风险
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作者 王晓琪 《西部论坛》 1995年第4期34-36,51,共4页
论风险与企业风险王晓琪自从人类社会产生以来,风险可以说是无时不有,无处不在。特别是第二次世界大战后,由于科学技术的迅猛发展,社会政治经济环境的动荡多变,使得企业所面临的风险在质上和量上都发生了极大变化。因此,当今的企... 论风险与企业风险王晓琪自从人类社会产生以来,风险可以说是无时不有,无处不在。特别是第二次世界大战后,由于科学技术的迅猛发展,社会政治经济环境的动荡多变,使得企业所面临的风险在质上和量上都发生了极大变化。因此,当今的企业只有认清了面临的各种风险,方能经... 展开更多
关键词 纯粹风险 风险管理者 投机风险 损失风险 企业风险管理 变异性 特殊风险 责任风险 数理性 不定性
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Gas sand distribution prediction by prestack elastic inversion based on rock physics modeling and analysis 被引量:5
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作者 贺芙邦 游俊 陈开远 《Applied Geophysics》 SCIE CSCD 2011年第3期197-205,240,共10页
Seismic inversion is one of the most widely used technologies for reservoir prediction. Many good results have been obtained but sometimes it fails to differentiate the lithologies and identify the fluids. However, se... Seismic inversion is one of the most widely used technologies for reservoir prediction. Many good results have been obtained but sometimes it fails to differentiate the lithologies and identify the fluids. However, seismic prestack elastic inversion based on rock physics modeling and analysis introduced in this paper is a significant method that can help seismic inversion and interpretation reach a new quantitative (or semi-quantitative) level from traditional qualitative interpretation. By doing rock physics modeling and forward perturbation analysis, we can quantitatively analyze the essential relationships between rock properties and seismic responses and try to find the sensitive elastic properties to the lithology, porosity, fluid type, and reservoir saturation. Finally, standard rock physics templates (RPT) can be built for specific reservoirs to guide seismic inversion interpretation results for reservoir characterization and fluids identification purpose. The gas sand distribution results of the case study in this paper proves that this method has unparalleled advantages over traditional post-stack methods, by which we can perform reservoir characterization and seismic data interpretation more quantitatively and efficiently. 展开更多
关键词 Rock physics seismic response elastic parameters elastic inversion reservoir characterization MODELING
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Reasoning complexity for extended fuzzy description logic with qualifying number restriction
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作者 陆建江 李言辉 +2 位作者 张亚非 周波 康达周 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期236-240,共5页
To solve the extended fuzzy description logic with qualifying number restriction (EFALCQ) reasoning problems, EFALCQ is discretely simulated by description logic with qualifying number restriction (ALCQ), and ALCQ... To solve the extended fuzzy description logic with qualifying number restriction (EFALCQ) reasoning problems, EFALCQ is discretely simulated by description logic with qualifying number restriction (ALCQ), and ALCQ reasoning results are reused to prove the complexity of EFALCQ reasoning problems. The ALCQ simulation method for the consistency of EFALCQ is proposed. This method reduces EFALCQ satisfiability into EFALCQ consistency, and uses EFALCQ satisfiability to discretely simulate EFALCQ satdomain. It is proved that the reasoning complexity for EFALCQ satisfiability, consistency and sat-domain is PSPACE-complete. 展开更多
关键词 extended fuzzy description logic qualifying number restriction reasoning complexity
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Analysis of radial basis function interpolation approach 被引量:4
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作者 邹友龙 胡法龙 +3 位作者 周灿灿 李潮流 李长喜 Keh-Jim Dunn 《Applied Geophysics》 SCIE CSCD 2013年第4期397-410,511,共15页
The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical prop... The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart. 展开更多
关键词 Inverse problems radial basis function interpolation new approach
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Triterpenoid Saponins from Eclipta prostrata L. 被引量:3
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作者 汤海峰 赵越平 +3 位作者 蒋永培 王忠壮 易杨华 雷其云 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期183-186,共4页
Five triterpenoid saponins were isolated from the Chinese traditional medicine Eclipta prostrata L.. On the basis of their chemical properties and spectral data, they were identified as eclalbasaponins II(1), I(2), II... Five triterpenoid saponins were isolated from the Chinese traditional medicine Eclipta prostrata L.. On the basis of their chemical properties and spectral data, they were identified as eclalbasaponins II(1), I(2), III(3), 3-O-[b-D-glucopyranosyl(12)-b-D-glucopyranosyl]-16a-ethoxy-olean-12-ene-28-oic acid-28-O-b-D-glu-copyranoside(4) and 3-O-[(2-O-sulfuryl-b-D-glucopyranosyl)(12)-b-D-glucopyranosyl]-echinocystic acid-28-O-b-D-glucopyranoside(5). Compounds 4 and 5 are new compounds and named eclalbasaponins XI and XII, respectively. Compounds 1 and 5 induced morphological deformation of Pyricularia oryzae mycelia. 展开更多
关键词 Eclipta prostrata Eclalbasaponin XI Eclalbasaponin XII Pyricularia oryzae BIOASSAY
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Some Notes of Property of Distribution Function of Many Variables
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作者 孔繁超 张曙光 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期60-64,共5页
In this paper we discuss a step further some convergence and continuity problems of distribution function on R^i. We give the following results: (1)distribution function F(x_1,…,x_k) on R^k is continuous if and only ... In this paper we discuss a step further some convergence and continuity problems of distribution function on R^i. We give the following results: (1)distribution function F(x_1,…,x_k) on R^k is continuous if and only if all marginal distribution functions of F is continuous on R^1. (2)If limF_n(x_1,……,x_k)=F(x_1,…,x_k) and limF_n(x_1—0,…,x_k—0)=F(x_1—0,…,x_k—0) at all non-continuity points of F, then 展开更多
关键词 probability space distribution function
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Classification of VxOy^q Clusters by △=2y+q-5x
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作者 马艳平 赵艳霞 +2 位作者 李子玉 丁迅雷 何圣贵 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期586-596,I0004,共12页
Vanadium oxide clusters VxOy^q(x≤8, q=0, ±1) are classified according to the oxidation index (△=2y+q-5x) of each cluster. Density functional calculations indicate that clusters with the same oxidation inde... Vanadium oxide clusters VxOy^q(x≤8, q=0, ±1) are classified according to the oxidation index (△=2y+q-5x) of each cluster. Density functional calculations indicate that clusters with the same oxidation index tend to have similar bonding characters, electronic structures, and reactivities. This general rule leads to the findings of new possible ground state struc- tures for V206 and V3O6+ clusters. This successful application of the classification method on vanadium oxide clusters proves that this method is very effective in studying the bonding properties of early transition metal oxide clusters. 展开更多
关键词 Vanadium oxide cluster Ground state structure Density functional calculation Oxidation index Bonding character
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:9
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作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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Local Bifurcation of a Thin Rectangle Plate with the Friction Support Boundary
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作者 叶敏 张伟亿 《Transactions of Tianjin University》 EI CAS 2002年第2期114-118,共5页
The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method... The dynamical equations of a thin rectangle plate subjected to the friction support boundary and its plane force are established in this paper. The local bifurcation of this system is investigated by using L S method and the singularity theory. The Z 2 bifurcation in non degenerate case is discussed. The local bifurcation diagrams of the unfolding parameters and the bifurcation response characters referred to the physical parameters of the system are obtained by numerical simulation. The results of the computer simulation are coincident with the theoretical analysis and experimental results. 展开更多
关键词 thin rectangle plate L S method singularity theory local bifurcation numerical simulation
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Solution of ODE u″+p(u)(u′)2+q(u)=0 and Applications to Classifications of All Single Travelling Wave Solutions to Some Nonlinear Mathematical Physics Equations 被引量:8
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作者 LIU Cheng-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期291-296,共6页
Under the travelling wave transformation, some nonlinear partial differential equations such as Camassa-Holm equation, High-order KdV equation, etc., are reduced to an integrable ODE expressed by u" +p(u)(u')^2... Under the travelling wave transformation, some nonlinear partial differential equations such as Camassa-Holm equation, High-order KdV equation, etc., are reduced to an integrable ODE expressed by u" +p(u)(u')^2 + q(u) = 0 whose generai solution can be given. Furthermore, combining complete discrimination system for polynomiai, the classifications of all single travelling wave solutions to these equations are obtained. The equation u"+p(u)(u')^2+q(u) = 0 includes the equation (u')^2 = f(u) as a special case, so the proposed method can be also applied to a large number of nonlinear equations. These complete results cannot be obtained by any indirect method. 展开更多
关键词 classification of travelling wave solution symmetry group nonlinear partial differential equation
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Liquid film falling behaviour on horizontal circular cylinder 被引量:3
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作者 CHUNG Han-shik K.Wusiman +5 位作者 KIM Seong-soo B.Nasan H.Afrianto Hafizur Rehman CHOI Du-youl JEONG Hyo-min 《Journal of Central South University》 SCIE EI CAS 2012年第5期1353-1358,共6页
The flow pattern behaviour of falling liquid film over three horizontal cylinders was evaluated.These flows can take three forms:discrete droplets,individual jets,and continuous sheet,and special attention is paid to ... The flow pattern behaviour of falling liquid film over three horizontal cylinders was evaluated.These flows can take three forms:discrete droplets,individual jets,and continuous sheet,and special attention is paid to the effects of the physical properties and geometrical parameters of the first two forms(droplets and jets) because these forms are more important in heat-transfer behaviour and less research has been published for these forms,The flow modes and experimental results were successfully compared with previous experimental literatures,and also the effects of liquid flow rate,tube diameter,and tube spacing on departure site spacing,in both drop and jet modes,were evaluated in the low Galileo number and high viscosity fluid(cooking oil),to help developing criteria for determining falling film modes and their transitions,and to understand the heat transfer characteristics associated with each mode. 展开更多
关键词 falling film flow mode CYLINDER
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Study of petrophysical parameter sensitivity from well log data 被引量:1
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作者 乔悦东 安鸿伟 《Applied Geophysics》 SCIE CSCD 2007年第4期282-287,共6页
Proper analysis of petrophysical parameter sensitivity from well log data can greatly improve the ability to discriminate hydrocarbon-bearing rocks. In this paper we discuss a petrophysical analysis method for the sel... Proper analysis of petrophysical parameter sensitivity from well log data can greatly improve the ability to discriminate hydrocarbon-bearing rocks. In this paper we discuss a petrophysical analysis method for the selection and application of higher sensitivity seismic attribute parameters to improve the ability to discriminate fluid and lithology. To better integrate with seismic interpretation, we construct a template to highlight rock physics parameters in sensitivity space, providing guidance for the quantitative seismic interpretation of hydrocarbon-bearing reservoirs. 展开更多
关键词 P-type parameters combined parameters sensitive parameters
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