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We review important studies in the field of stratosphere-ionosphere coupling, including recent studies of wave motions of planetary waves, atmospheric tides and internal gravity waves in the atmosphere. The interrelation between stratospheric sudden warmings and winter anomaly of radio absorption, a dynamical model of stratospheric sudden warmings and some production mechanisms of intensified electron density in the D region are discussed. Other topics presented are atmospheric tides in the lower thermosphere including dynamo action, and internal gravity waves, by which we intend to explain travelling ionospheric disturbances in the F 2 region and sporadic E layer at midlatitude (wave-enhanced sporadic E). Thermospheric winds are also reviewed and wind effects on the F 2 layer are discussed. For each atmospheric event systematic observations of suitable physical quantities with proper time and spatial intervals are desirable.  相似文献   
2.
We estimate the capability of ozone (O3) retrieval with the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) instrument attached to the Exposed Facility of the Japanese Experiment Module (JEM) on the International Space Station (ISS). SMILES carries a 4-K mechanical refrigerator to cool superconducting devices in space. Since SMILES has high sensitivity thanks to the superconducting receiver, it is expected that SMILES has ability to retrieve O3 profiles more precisely than the previous millimeter–submillimeter limb measurements from satellites.  相似文献   
3.
Seedlings of cucurbitaceous plants develop a protuberant tissue, or peg, on the lower side of the transition region between root and hypocotyl when germinated in a horizontal position. Peg develops due to a change in growth polarity of the cortical cells. We have examined the role of the cytoskeletal structure in peg formation of cucumber seedlings. We observed that in both peg and normal cortical cells of 36 h-old seedlings the microtubules (MTs) were arranged perpendicular to the longitudinal axis of the elongating cells. Application of colchicine perturbed the MTs structure and inhibited the formation of pegs. In 20 h-old seedlings, MTs in cortical cells destined to be a peg tissue had no preferential organization, whereas MTs in normal cortical cells were transversely oriented. After 24 h, the MTs in future peg cells were arranged similar to those of 36 h-old seedlings, although the initiation of peg tissue was not yet visible. These results suggest that reorganization of MTs is required for peg formation and causes the change in growth polarity of the cortical cells.  相似文献   
4.
使用面包板模型和仿真方法,在实验室内研究月球指向就位测量望远镜(ILOM)的基本特征,如望远镜星像中心点位置精度、温度效应、倾斜以及地面震动的影响。使用这个技术预期在月球表面观测月球自转时可以达到1ms的精度。将在地面上开展测试验证观测以全面评价达到优于0.1″观测精度目标所需条件和特征。  相似文献   
5.
The balloon-borne very long baseline interferometry (VLBI) experiment is a technical feasibility study for performing radio interferometry in the stratosphere. The flight model has been developed. A balloon-borne VLBI station will be launched to establish interferometric fringes with ground-based VLBI stations distributed over the Japanese islands at an observing frequency of approximately 20?GHz as the first step. This paper describes the system design and development of a series of observing instruments and bus systems. In addition to the advantages of avoiding the atmospheric effects of absorption and fluctuation in high frequency radio observation, the mobility of a station can improve the sampling coverage (“uv-coverage”) by increasing the number of baselines by the number of ground-based counterparts for each observation day. This benefit cannot be obtained with conventional arrays that solely comprise ground-based stations. The balloon-borne VLBI can contribute to a future progress of research fields such as black holes by direct imaging.  相似文献   
6.
研究主要着眼于双层供应链结构中用于多计划时间段批量生产计划的基于谈判的协作计划过程,其主要目的是为了研究基于谈判的协作计划过程对优化购买方本地计划,并最终得到较好的花费和服务所起到的作用。研究通过建立一组数学模型对此问题进行模拟计算及结果分析,所使用的数学模型中,购买者与供应商之间只需要交换有限的信息来进行购买者的本地计划和整个协作计划过程。研究表明该方法对协助供应链中成员制定有效的生产计划具有一定的指导作用,可通过对制约条件的扩展后在整体供应链中推广使用。  相似文献   
7.
We numerically examined various retroreflectors as laser ranging targets for future missions to the Moon. The geometric conditions, such as the angle of incidence and velocity aberration, with lunar targets are much more restricted than those with most of the earth-orbiting artificial satellites. The numerical optical response simulation carried out in this study indicates that a single retroreflector with a diameter of 150–250 mm performs similar to the existing Apollo retroreflector arrays. Further, no dihedral angle is required for small retroreflectors with diameters below 150 mm for uncoated ones and below 100 mm for coated and hollow ones. Retroreflectors with larger diameters require dihedral angles of 0.20, 0.25, and 0.35 arcsec for coated, uncoated and hollow types, respectively. The objective of this fundamental study is to underlie the development of future laser ranging targets that are to be placed on the Moon.  相似文献   
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