By the use of the transformations of physical plane to strain plane and physical planeto stress plane,an analytic expression of the asymptotic solution near a modeⅢcrack tipin a power hardening medium can be obtained...By the use of the transformations of physical plane to strain plane and physical planeto stress plane,an analytic expression of the asymptotic solution near a modeⅢcrack tipin a power hardening medium can be obtained.In this paper the effectiveness of thetransformation is discussed.Analytical results show that the transformation is effectiveexcept for a special limit case of power hardening media—the ideal plastic materials.展开更多
A study has been made on the reflected and transmitted powers generated when an arbitrarily polarized plane wave impinges at a planar interface separating an isotropic achiral medium(IAM) and an isotropic chiral mediu...A study has been made on the reflected and transmitted powers generated when an arbitrarily polarized plane wave impinges at a planar interface separating an isotropic achiral medium(IAM) and an isotropic chiral medium(ICM). It follows that the theoretical formulas are derived for the normalized reflection and transmission powers from an IAM–ICM interface for an arbitrary polarized incident wave, and those at an ICM–IAM interface for right-hand circularly polarized(RCP) or left-hand circularly polarized(LCP) incident wave are also obtained. The behavior of the reflected and transmitted waves in different cases is studied, and the dependence of the reflection/transmission of the incident wave on the incident angle and the parameters of the media is investigated in detail. Our numerical results show that high transmission is exhibited under the impedance matching condition and the incident wave can be split into two waves of the same circular polarization state in the case of the ICM–IAM interface, which indicates that circular polarizing beam splitter is achieved.展开更多
The steady oil production and pressure distribution formulae of vertically fractured well for power-law non-Newtonian fluid were derived on the basis of the elliptic flow model in fractal reservoirs. The corresponding...The steady oil production and pressure distribution formulae of vertically fractured well for power-law non-Newtonian fluid were derived on the basis of the elliptic flow model in fractal reservoirs. The corresponding transient flow in fractal reservoirs was studied by numerical differentiation method: the influence of fractal index to transient pressure of vertically fractured well was analyzed. Finally the approximate analytical solution of transient flow was given by average mass conservation law. The study shows that using elliptic flow method to analyze the flow of vertically fractured well is a simple method.展开更多
Media power,the impact that media have on public opinion and perspectives,plays a significant role in maintaining internal stability,exerting external influence,and shaping international dynamics for nations/regions.H...Media power,the impact that media have on public opinion and perspectives,plays a significant role in maintaining internal stability,exerting external influence,and shaping international dynamics for nations/regions.However,prior research has primarily concentrated on news content and reporting time,resulting in limitations in evaluating media power.To more accurately assess media power,we use news content,news reporting time,and news emotion simultaneously to explore the emotional contagion between media.We use emotional contagion to measure the mutual influence between media and regard the media with greater impact as having stronger media power.We propose a framework called Measuring Media Power via Emotional Contagion(MMPEC)to capture emotional contagion among media,enabling a more accurate assessment of media power at the media and national/regional levels.MMPEC also interprets experimental results through correlation and causality analyses,ensuring explainability.Case analyses confirm the higher accuracy of MMPEC compared to other baseline models,as demonstrated in the context of COVID-19-related news,yielding compelling and interesting insights.展开更多
With the development of globalization and gradual intensification of mutual dependence of the world, "hard power" which includes economic and military strength is no longer the primary consideration for many...With the development of globalization and gradual intensification of mutual dependence of the world, "hard power" which includes economic and military strength is no longer the primary consideration for many countries. They tend to pay more attention to the attractiveness of their "soft power",which includes values,life style , ideology and so forth. Just as Joseph S. Ny , the famous professor of Harvard who puts forward the concept of soft power, says ,"only by widespread communication and diffusion can a country reinforces its soft power". This is mass media's function. Since the 1990s, tens of thousands cultural products brought in from America are exported to foreign countries, including popular music, films ,TV programs, magazines, books and so forth. By making advantage of its monopoly position in media circle, the United States pursues cultural hegemonism and expands its popular culture all over the world. This thesis takes a general view of the great advantages of America multi-national media groups and how they push forward the American popular culture all over the world.展开更多
文摘By the use of the transformations of physical plane to strain plane and physical planeto stress plane,an analytic expression of the asymptotic solution near a modeⅢcrack tipin a power hardening medium can be obtained.In this paper the effectiveness of thetransformation is discussed.Analytical results show that the transformation is effectiveexcept for a special limit case of power hardening media—the ideal plastic materials.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61431010 and 61501350)the National Key Basic Research Program of China(Grant No.2014CB340203)
文摘A study has been made on the reflected and transmitted powers generated when an arbitrarily polarized plane wave impinges at a planar interface separating an isotropic achiral medium(IAM) and an isotropic chiral medium(ICM). It follows that the theoretical formulas are derived for the normalized reflection and transmission powers from an IAM–ICM interface for an arbitrary polarized incident wave, and those at an ICM–IAM interface for right-hand circularly polarized(RCP) or left-hand circularly polarized(LCP) incident wave are also obtained. The behavior of the reflected and transmitted waves in different cases is studied, and the dependence of the reflection/transmission of the incident wave on the incident angle and the parameters of the media is investigated in detail. Our numerical results show that high transmission is exhibited under the impedance matching condition and the incident wave can be split into two waves of the same circular polarization state in the case of the ICM–IAM interface, which indicates that circular polarizing beam splitter is achieved.
文摘The steady oil production and pressure distribution formulae of vertically fractured well for power-law non-Newtonian fluid were derived on the basis of the elliptic flow model in fractal reservoirs. The corresponding transient flow in fractal reservoirs was studied by numerical differentiation method: the influence of fractal index to transient pressure of vertically fractured well was analyzed. Finally the approximate analytical solution of transient flow was given by average mass conservation law. The study shows that using elliptic flow method to analyze the flow of vertically fractured well is a simple method.
基金supported by the National Natural Science Foundation of China(No.62127808).
文摘Media power,the impact that media have on public opinion and perspectives,plays a significant role in maintaining internal stability,exerting external influence,and shaping international dynamics for nations/regions.However,prior research has primarily concentrated on news content and reporting time,resulting in limitations in evaluating media power.To more accurately assess media power,we use news content,news reporting time,and news emotion simultaneously to explore the emotional contagion between media.We use emotional contagion to measure the mutual influence between media and regard the media with greater impact as having stronger media power.We propose a framework called Measuring Media Power via Emotional Contagion(MMPEC)to capture emotional contagion among media,enabling a more accurate assessment of media power at the media and national/regional levels.MMPEC also interprets experimental results through correlation and causality analyses,ensuring explainability.Case analyses confirm the higher accuracy of MMPEC compared to other baseline models,as demonstrated in the context of COVID-19-related news,yielding compelling and interesting insights.
文摘With the development of globalization and gradual intensification of mutual dependence of the world, "hard power" which includes economic and military strength is no longer the primary consideration for many countries. They tend to pay more attention to the attractiveness of their "soft power",which includes values,life style , ideology and so forth. Just as Joseph S. Ny , the famous professor of Harvard who puts forward the concept of soft power, says ,"only by widespread communication and diffusion can a country reinforces its soft power". This is mass media's function. Since the 1990s, tens of thousands cultural products brought in from America are exported to foreign countries, including popular music, films ,TV programs, magazines, books and so forth. By making advantage of its monopoly position in media circle, the United States pursues cultural hegemonism and expands its popular culture all over the world. This thesis takes a general view of the great advantages of America multi-national media groups and how they push forward the American popular culture all over the world.