特大型工程项目有形产权的形成机理

特大型工程项目有形产权的形成,是形成新增企业财产权产权的过程和行为,其产权性质区别于工程技术角度的理解。包括适应企业发展战略需要是内在动因;是一种强制性的企业产权制度安排;产权内容决定新增企业财产权的未来市场价值;有形产权的形成效率与交易成本、代理人能力密切相关;有形产权的形成效率反映了现代企业制度的效率等多因素形成机理。为适应有形产权形成的需要,应构建一套有效降低交易成本的投资管理体系。     

Coronal Dynamics and the AIA on SDO

We provide a brief overview of present-day studies of inner corona dynamics, with examples of mass ejections (CME), flares and active region dynamics. While the names of the topics have not changed in several decades, the internal details and the language used to express the nature of the problem have changed considerably. We conclude with a short discussion of the contribution to studies of coronal dynamics to be expected from the Atmospheric Imager Assembly (AIA) on the Solar Dynamics Observatory.     

Impact of Solar Activity on Stratospheric Ozone and NO2 Observed by Gomos/Envisat

Energetic proton precipitation occurring during solar events can increase the production of odd nitrogen in the upper stratosphere and mesosphere. A very intense solar proton event (SPE) occurred on 28 October 2003. Its impact on the composition of the middle atmosphere was observed in details due to the availability of several space instruments. Here we present GOMOS observations of a strong NO₂increase and a related ozone decrease in the upper stratosphere at north polar latitude. The perturbation of the chemical composition of the stratosphere was observed until the middle of December 2003. A strong NO₂ increase was also observed in the south polar vortex in June-July 2003. It is tentatively attributed to the effect of an SPE with protons of moderate energy occurring on 29 May 2003. If this hypothesis is confirmed, it will imply that the global effect of SPEs on the composition of the stratosphere is underestimated when only strong energy SPEs are considered.     

太阳活动区R9077引起的强烈吸收事件

利用南极中山站的观测数据分析了太阳活动区R9077所引起的强烈吸收事件，其中2000年7月14日的太阳质子事件引起了持续3天多强烈的极盖吸收，同时，激烈的太阳活动使磁层处于极度扰动状态，磁层高能粒子沉降使许多持续时间较短的吸收峰叠加在极盖吸收背景之上，最突出的是7月1日的吸收增强事件，其最大值达26dB。这是自1997年2月中山站安装成像式宇宙噪声接收机以来观测到的最强的吸收，另一个较突出的吸收峰发生在14日1753UT前后，本文还讨论了产生这些吸收的原由。     

What is the optimum solar proxy for long-term ionospheric investigations?

The problem of optimum solar proxy is important for long-term and/or climatological studies of ionospheric parameters. Here we focus on possibly different optimum solar proxies for different ionospheric parameters, as they are affected by partly different spectral ranges of solar ionizing radiation. We use yearly average values of foF2 and foE of four European stations with long (1976–2014) and high-quality data (Juliusruh, Pruhonice, Rome, Slough/Chilton), and the global total electron content (G-TEC). Four solar proxies are used: F10.7, Mg II, solar Lymna-alpha flux Fα and sunspot numbers. The most important finding is that the optimum solar proxies are different for different ionospheric parameters. The most suitable solar proxy for foF2 is found to be Mg II, whereas for foE F10.7 evidently outperforms Mg II. Fα and sunspot numbers perform slightly worse but none of four solar proxies performs poorly. F10.7 is favored for G-TEC, to some extent surprisingly, as previous results favored rather Mg II.     

The interconnection and phase asynchrony between the geomagnetic indices’ periodicities: A study based on the interplanetary magnetic field polarities 1967–2018 utilizing a cross wavelet analysis

In this article, we investigate the interconnection and phase asynchrony between the periodicities of geomagnetic activity indices Kp, Ap, aa, and Dst according to the interplanetary magnetic field (IMF) polarities, toward (T) or away (A), during the time interval 1967–2018. For this purpose, the daily data of Kp, Ap, aa, and Dst indices during the considered period have been sorted into two groups (T and A) according to the IMF polarities. The wavelet transform (WT), the cross-wavelet transform (XWT), and the wavelet coherence (WTC) have been applied on the monthly averages of T and A groups for each geomagnetic index. Moreover, the correlation analyses (linear and running correlations) between the annual averages of T and A groups of each geomagnetic index have been investigated. The results of XWT and WTC revealed the existence of a long-term periodicity in the frequency range 8–16 yr for the monthly averages of T and A groups for aa, Kp, and Ap indices existed during the entire period. In contrast, the Dst index revealed this periodicity during the period 1980–2018. In addition, during this frequency band, both T and A groups of each geomagnetic index revealed a highly positive correlation and nearly in-phase relationship behavior. Furthermore, during the frequency band 4–8 yr, the XWT displayed a prominent periodicity that occurred for the monthly averages of T and A groups of each geomagnetic index, revealing a phase change during some time intervals. Periodicity in the range 2–4 yr for the monthly averages of T and A groups of aa, Kp_, Ap, and Dst occurred in the intervals; 1967–2009 for aa and Kp, 1967–2007 for Ap, and 1976–1995 for Dst. The annual periodicity is also identified for all considered indices. Both T and A groups of Dst shared a semiannual periodicity (~187 days) during different intervals in the entire period. On the other hand, a periodicity around 0.25-yr (~90 days) appeared only near the times of solar activity maxima in the case of the T and A groups of aa, Kp, and Ap indices.     

A note on the relationship between sunspot numbers and active days

We have studied the relationship between three different versions of the sunspot number (Group, International and American Sunspot Number) and the number of active days (i.e., the number of days with spots on the solar disk). We have detected an approximately linear relationship for low solar activity conditions. However, this relationship for the International Sunspot Number is very different to the ones obtained with the other versions of the sunspot number. The discordant values correspond to older observations.     

Dynamics of global electron content in 1998–2005 derived from global GPS data and IRI modeling

We analyzed the dynamics of global electron content (GEC) for the period 1998–2005 and compared the estimated GEC with variations of the 10.7-cm solar radio emission and with and with GEC values obtained with IRI-2001. We found a strong resemblance between the curves’ shapes for the experimental and modeled GEC: strong semiannual variations are discernible in these series and both curves tend to increase the absolute GEC value during the period of maximum of solar activity. However, there are some significant distinctions, such as absence of 27-day fluctuations in the series of GEC computed by the IRI-2001. On the contrary, observational GEC reflects well dynamics of solar activity: 27-day variations of GEC are very similar to the ones of the index F10.7, but GEC undergoes a lagging of about of 30–60 h as compared to value of the F10.7 index. The relative amplitude of 27-day variations decreases from 8% at the rising and falling solar activity to 2% at the period of its maximum.     

Debris flux comparisons from the Goldstone Radar,Haystack Radar,and Hax Radar prior,during, and after the last solar maximum

The continual monitoring of the low Earth orbit (LEO) debris environment using highly sensitive radars is essential for an accurate characterization of these dynamic populations. Debris populations are continually evolving since there are new debris sources, previously unrecognized debris sources, and debris loss mechanisms that are dependent on the dynamic space environment. Such radar data are used to supplement, update, and validate existing orbital debris models. NASA has been utilizing radar observations of the debris environment for over a decade from three complementary radars: the NASA JPL Goldstone radar, the MIT Lincoln Laboratory (MIT/LL) Long Range Imaging Radar (known as the Haystack radar), and the MIT/LL Haystack Auxiliary radar (HAX). All of these systems are highly sensitive radars that operate in a fixed staring mode to statistically sample orbital debris in the LEO environment. Each of these radars is ideally suited to measure debris within a specific size region. The Goldstone radar generally observes objects with sizes from 2 mm to 1 cm. The Haystack radar generally measures from 5 mm to several meters. The HAX radar generally measures from 2 cm to several meters. These overlapping size regions allow a continuous measurement of cumulative debris flux versus diameter from 2 mm to several meters for a given altitude window. This is demonstrated for all three radars by comparing the debris flux versus diameter over 200 km altitude windows for 3 nonconsecutive years from 1998 to 2003. These years correspond to periods before, during, and after the peak of the last solar cycle. Comparing the year to year flux from Haystack for each of these altitude regions indicate statistically significant changes in subsets of the debris populations. Potential causes of these changes are discussed. These analysis results include error bars that represent statistical sampling errors.     

Stratospheric polar vortex as a possible reason for temporal variations of solar activity and galactic cosmic ray effects on the lower atmosphere circulation

Possible reasons for the temporal instability of long-term effects of solar activity (SA) and galactic cosmic ray (GCR) variations on the lower atmosphere circulation were studied. It was shown that the detected earlier ∼60-year oscillations of the amplitude and sign of SA/GCR effects on the troposphere pressure at high and middle latitudes (Veretenenko and Ogurtsov, Adv.Space Res., 2012) are closely related to the state of a cyclonic vortex forming in the polar stratosphere. The intensity of the vortex was found to reveal a roughly 60-year periodicity affecting the evolution of the large-scale atmospheric circulation and the character of SA/GCR effects. An intensification of both Arctic anticyclones and mid-latitudinal cyclones associated with an increase of GCR fluxes at minima of the 11-year solar cycles is observed in the epochs of a strong polar vortex. In the epochs of a weak polar vortex SA/GCR effects on the development of baric systems at middle and high latitudes were found to change the sign. The results obtained provide evidence that the mechanism of solar activity and cosmic ray influences on the lower atmosphere circulation involves changes in the evolution of the stratospheric polar vortex.