5 resultados para Sitting

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Data regarding the sexual behavior of black-and-white snub-nosed monkeys (Rhinopithecus bieti) were collected in 1998 in a one-male unit in captivity by all-occurrences sampling during the mating season. Before the present study, little was known about the sexual behavior of this species. This study showed that female solicitation is mainly expressed as "prostration plus glancing laterally" (PG) or "sitting plus head moving up and down" (HM), and male solicitation is exhibited by the "grunt bared-teeth display." The mount-to-ejaculation ratio was 5.2 on average, and single-mount ejaculations (SMEs) were observed in only 4.4% of mounts on days with at least one ejaculation. Therefore, the main copulatory pattern of this species is multiple-mount ejaculation (MME). Females initiated 72% of 18 ejaculatory mounts. Females initiated more ejaculatory mounts than non-ejaculatory ones. In general, the patterns of sexual behavior in this species are similar to those reported for other Colobines. (C) 2004 Wiley-Liss, Inc.

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观察点设置问题是地形可视性分析中的一类重要问题,对该问题的研究可以在空间信息辅助决策、通信、旅游、野生动物保护等领域发挥重大作用。本文在对地形可视性分析中观察点设置问题现有研究成果总结和分析基础上对该问题展开深入研究。 首先,针对现有解决方法只从智能算法或地形数据表示方法单一角度进行分析和研究的局限性,提出了一种问题相关的智能算法和数据表示方法相结合的解决问题新框架。该框架考虑了解决观察点设置问题时智能算法的优点和数据表示方式的特点相互配合问题,目的是充分发挥二者各自的优势以提高观察点设置问题解决的准确度与效率。 其次,在深入分析观察点设置问题本身特点的基础上,结合隶属云理论的基本理论和方法,对经典模拟退火算法从退温函数设计、温度产生过程、状态生成过程三方面进行了问题相关的改进,提出了一种适于观察点设置问题的改进模拟退火算法(Improved Simulated Annealing algorithm, ISA)。该算法一方面保持了经典模拟退火算法的稳定倾向特性,保证了算法满足伴随退火温度的不断下降,对恶化的新状态越来越难于接受这一模拟退火算法的最基本特征;另一方面其退火温度的连续性随机变化特性和隐含的“回火升温”过程,则有利于算法有效拒绝恶化解,加速算法收敛,能够更好地满足观察点设置问题对于算法收敛速度的要求。 再次,在分析地形数据的精度、误差等因素对观察点设置问题的解决准确性和解决效率影响程度的基础上,提出了一种基于离散余弦变换的地形数据内插方法(Discrete Cosine Transformation Interpolation method, DCTI)。新方法将传统空域上的地形内插转换到变换域上进行,同时充分利用了离散余弦变换的熵保持特性和能量压缩特性,简化了变换域上的内插过程,提高了地形数据内插的效率和精度。DCTI方法与其他现有典型地形数据内插方法相比,对地形可视性信息获取的准确性和效率影响最小,为平衡观察点设置问题解决过程中时间效率和准确度之间的关系,最终有效地解决观察点设置问题提供了数据基础。 最后,从智能算法和地形数据相结合的角度出发,提出了一种基于ISA和DCTI相结合的观察点设置问题多分辨率处理方法(Multi-Resolution Processing method, MRP)。新方法将模拟退火算法的逐次退火特点和地形数据的多分辨率表示充分结合,达到了发挥算法数据相结合的综合优势的目的。与现有单纯基于模拟退火算法的解决方法相比,在问题解决准确度保持不变的前提下,基于MRP方法的观察点设置问题解决的平均耗时减少85%~95%,为实际工程应用问题的解决提供了一条重要途径。

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We study here the reactions between C-60 and planar C5H5+ cations that lead to the formation of [C60C5H5](+) adduct cations in the chemical ionization source of the mass spectrometer. The structures, stabilities and charge locations of some possible isomers of [C60C5H5](+): sigma-adduct, pi-complex, [1,4]- and [1,2]-addition cations, are studied by AM1 semiempirical molecular orbital calculations. We find that the most stable is the sigma-addition cation. Another interesting and stable structure is the pi-complex cation which is bonded by the electrostatic interaction at the inter-ring distance of 1.589 Angstrom with the C-5v symmetry. The C5H5+ cyclopentadienium cation seems to be an ''inverted umbrella'' sitting on a five-membered ring of the C-60 cage.

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As a kind of strategic resource,petroleum play an very important role in current social stability, economic development and state safety. Since 1993 China has turned from a net oil exporter into a net oil importer, the figure of imported oil increased from then on. In 2004 China's total energy consumption exceeded Japan’s, and ranked in the second place, just inferior to America. Today China is the world’s third-largest importing nation, accounting for 6% of world imports and 8% of world consumption. Comparing with other strategic petroleum reserve schemes, underground oil storage possess many advantages, such as security, economy, less pollution, save land, suited for strategic reserve and so on, so it is the most ideal form for strategic petroleum reserve. In the background of China Strategic Petroleum Reserve Program started just now, this paper choose Circum-Bo sea region as a study area, and do some system study on the underground oil storage caverns constructed in inter-large granite rock masses in Circum-Bo sea region. On the foundation of a great amount of information come from both home and abroad, firstly this paper analysed the principle, economy, cavern shape, profile dimension, and gain some cognizances and logos, as follows: ①Hard rock mass such as granite is the major rock, in which underground oil storage are constructed; ②Unlined underground oil storage caverns had been wide spread used as a sort of oil storage form abroad, there already exist a suit of skilled experience and technologies to prevent oil product from leaking; ③Compared with surface tanks, underground oil storage cavern possess predominance in economy clearly. In general, it will be more economical when the storage capacity exceed 50000m3. The quality of rock mass is the most important factor for underground storage cost, however such as hydrogeology, storage capacity, the number of storage galleries, the length, storage product, mechanical equipments, geographic location also influent the cost. In designed depth of the underground storage, the rock mass of Jinzhou mainly belong to class Ⅱ, but parts with dykes, clayization alteration, and dense joints are Ⅲ, Ⅳ; ④Now, there are few underground oil storages span more than 25m in both abroad and home. The examples of some ancient underground works and modern underground excavation with wide span surely give us many precious elicitations to construct more great unlined storage caverns, when the rock mass quality is good, cavern shape and construction method also are proper, it is quite possible to construct underground oil storage cavern with span more than 30m . The main axis orientation of Jinzhou underground oil storage cavern is NW direction, the cavern's elevation locate between -53msl and -76msl. The storage's total volume is about 3×106m3, composed of 8 parallel galleries with 950m length, the pillars between them are 45m, and every two of galleries form one unit, which can deposit 75×104m3 for each unit. The product will be stored are Saudi light and Saudi medium crude oil, the main cavern's section is 411.5m2, with 23m height and 19m width. According to the principle and technique of engineering geomechanics, this study supply a sort of system scientific thinking and method for sitting location of underground oil storage in granite region: ① On the foundation of the earth crust stability sub-zone appraise of Circum-Bo sea region, farther research concerning granite distribution, genesis, geological period and fault structure are conducted in stable areas, generally, this paper select Liaoxi, east shore of Liaotung peninsula and Jiaotung peninsula as target areas for underground oil storage regions, where Mesozoic granite is magnitude; ②After roundly comparison in facts of geologic structure, engineering geology, hydrogeology, topography, transportation and so on of three granite distributed areas, at last, selecting Jingzhou granite zone in Liaoxi out as an ideal construction area; ③ Detailed investigation is conducted in the southeast of Baimashi in Jingzhou development district, the final field. Ultrasonic Borehole Television, as a major way to collect original information of borehole rock mass were used, which is very effective to appraise the quality of deep rock mass; ④ According to the field data of tectonic stress, rock mass quality, the spatial distribution of fracture water, some optimum designs in cross section, axial direction and cavern span have been designed for the underground oil storage cavern layout in Jinzhou. To understand the characteristics of swelling alteration rock in Jinzhou granite mass, collected abundant swelling alteration rock engineering examples in granite, which study them in detail, concluded the swelling alteration rock distribute nearly everywhere in China, intruded medium-basic dykes alteration, along discontinuities and mineral hydrothermal alteration with genesis of granite are three main forms clayization alteration rock in granite rock mass. In Jinzhou field, from macro to micro studied the swelling rock which induced by mid-basic dyke intrusion, with weak swelling. In conclusion, this paper conclude the distribution rule and features of expansion alteration rock in filed, and advise some technical suggestions for excavation at swelling alteration rock part. The main features of this paper: ①In the process of site selection, investigation and design, a suit of technique and method of engineering geomechanics metasynthesis were formed, which is significative to guide the large scale underground oil storage cavern sitting location, investigation and design in granite rock mass; ②The detailed discussion on the engineering geology problems in granite mass, such as weathering crust, faults, dykes and clayization alteration rock, are useful for other projects in aspects of site selection, engineering geology evaluation and stability estimation; ③The summary and integration of the genesis, type, countermeasure relate to swelling alteration rock, also is likely to be used for other underground oil storage caverns constructed in swelling alteration granite. In conclusion, this study is meaningful for guiding the large scale underground oil storage for site selection, investigation and design in granite rock mass.