Using a relationship between Hubble’s “parameter”, Temperature, Energy and effective mass, from there obtain in 3 + 1 dimensions a relationship between effective mass, and the initial degrees of freedom, to the 1/4...Using a relationship between Hubble’s “parameter”, Temperature, Energy and effective mass, from there obtain in 3 + 1 dimensions a relationship between effective mass, and the initial degrees of freedom, to the 1/4<sup>th</sup> power, we will discuss candidates for entry into this, assuming for a start that initial universe conditions are similar to a black hole, i.e. a nearly singular start to inflationary expansion;this would necessitate a HUGE initial degree of freedom value as outlined in our argument.展开更多
在新闻学上,Freedom of the press是个非常重要的术语,其基本内涵是新闻自由,然而对它的翻译却存在很大的差异。原因主要有二,一是Freedom of the press的内涵随媒介形态的变化而变化,二是Press本身具有多重的词义。本文从社会变迁和语...在新闻学上,Freedom of the press是个非常重要的术语,其基本内涵是新闻自由,然而对它的翻译却存在很大的差异。原因主要有二,一是Freedom of the press的内涵随媒介形态的变化而变化,二是Press本身具有多重的词义。本文从社会变迁和语言学角度进行分析,认为把Freedom of the press译为新闻自由是适宜的。展开更多
Unlike most previous studies on the transverse vortex-induced vibration(VlV) of a cylinder mainly under the wallfree condition (Williamson & Govardhan, 2004), this paper experimentally investigates the vortex-ind...Unlike most previous studies on the transverse vortex-induced vibration(VlV) of a cylinder mainly under the wallfree condition (Williamson & Govardhan, 2004), this paper experimentally investigates the vortex-induced vibration of a cylinder with two degrees of freedom near a rigid wall exposed to steady flow. The amplitude and frequency responses of the cylinder are discussed. The lee wake flow patterns of the cylinder undergoin^g VIV were visualized by employing the hydrogen bubble technique. The effects of the gap-to-diameter ratio (eo/D) and the mass ratio on the vibration amplitude and frequency are analyzed. Comparisons of VIV response of the cylinder are made between one degree (only transverse) and two degrees of freedom (streamwise and transverse) and those between the present study and previous ones. The experimental observation indicates that there are two types of streamwise vibration, i.e. the first streamwise vibration (FSV) with small amplitude and the second streamwise vibration (SSV) which coexists with transverse vibration. The vortex shedding pattern for the FSV is approximately syrmnetric and that for the SSV is ahernate. The first streamwise vibration tends to disappear with the decrease of eo/D. For the case of large gap-to-dianeter ratios ( e.g. eo/D = 0. 54 ~ 1.58), the maximum amplitudes of the second streamwise vibration and transverse one increase with the increasing gap- to-diameter ratio. But for the case of small gap-to-diameter ratios (e. g. eo/D= 0. 16, 0.23), the vibration amplitude of the cylinder increases slowly at the initial stage (i.e. at small reduced velocity Vr), and across the maximum amplitude it decreases quickly at the last stage (i.e. at large Vr). Within the range of the examined small mass ratio (m 〈 4), both streamwise and transverse vibration amplitude of the cylinder decrease with the increase of mass ratio for the fixed value of Vr- The vibration range ( in terms of Vr) tends to widen with the decrease of the mass ratio. In the second streamwise vibration region, the vibration frequency of the cylinder with a small mass ratio ( e.g. mx = 1.44) undergoes a jump at a certain Vr+ The maximum amplitudes of the transverse vibration for two-degree-of-freedom case is larger than that for one-degree-of-freedom case, but the transverse vibration frequency of the cylinder with two degrees of freedom is lower than that with one degree of freedom(transverse).展开更多
文摘Using a relationship between Hubble’s “parameter”, Temperature, Energy and effective mass, from there obtain in 3 + 1 dimensions a relationship between effective mass, and the initial degrees of freedom, to the 1/4<sup>th</sup> power, we will discuss candidates for entry into this, assuming for a start that initial universe conditions are similar to a black hole, i.e. a nearly singular start to inflationary expansion;this would necessitate a HUGE initial degree of freedom value as outlined in our argument.
文摘在新闻学上,Freedom of the press是个非常重要的术语,其基本内涵是新闻自由,然而对它的翻译却存在很大的差异。原因主要有二,一是Freedom of the press的内涵随媒介形态的变化而变化,二是Press本身具有多重的词义。本文从社会变迁和语言学角度进行分析,认为把Freedom of the press译为新闻自由是适宜的。
基金supported by the Eleventh Five-Year Plan of Chinese Academy of Sciences(Grant No.KJCX2-YW-L02) the National Natural Science Foundation of China (Grant No.50509022)
文摘Unlike most previous studies on the transverse vortex-induced vibration(VlV) of a cylinder mainly under the wallfree condition (Williamson & Govardhan, 2004), this paper experimentally investigates the vortex-induced vibration of a cylinder with two degrees of freedom near a rigid wall exposed to steady flow. The amplitude and frequency responses of the cylinder are discussed. The lee wake flow patterns of the cylinder undergoin^g VIV were visualized by employing the hydrogen bubble technique. The effects of the gap-to-diameter ratio (eo/D) and the mass ratio on the vibration amplitude and frequency are analyzed. Comparisons of VIV response of the cylinder are made between one degree (only transverse) and two degrees of freedom (streamwise and transverse) and those between the present study and previous ones. The experimental observation indicates that there are two types of streamwise vibration, i.e. the first streamwise vibration (FSV) with small amplitude and the second streamwise vibration (SSV) which coexists with transverse vibration. The vortex shedding pattern for the FSV is approximately syrmnetric and that for the SSV is ahernate. The first streamwise vibration tends to disappear with the decrease of eo/D. For the case of large gap-to-dianeter ratios ( e.g. eo/D = 0. 54 ~ 1.58), the maximum amplitudes of the second streamwise vibration and transverse one increase with the increasing gap- to-diameter ratio. But for the case of small gap-to-diameter ratios (e. g. eo/D= 0. 16, 0.23), the vibration amplitude of the cylinder increases slowly at the initial stage (i.e. at small reduced velocity Vr), and across the maximum amplitude it decreases quickly at the last stage (i.e. at large Vr). Within the range of the examined small mass ratio (m 〈 4), both streamwise and transverse vibration amplitude of the cylinder decrease with the increase of mass ratio for the fixed value of Vr- The vibration range ( in terms of Vr) tends to widen with the decrease of the mass ratio. In the second streamwise vibration region, the vibration frequency of the cylinder with a small mass ratio ( e.g. mx = 1.44) undergoes a jump at a certain Vr+ The maximum amplitudes of the transverse vibration for two-degree-of-freedom case is larger than that for one-degree-of-freedom case, but the transverse vibration frequency of the cylinder with two degrees of freedom is lower than that with one degree of freedom(transverse).