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支撑结构对实尺度潮流能水轮机性能影响研究
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作者 张金辉 谭俊哲 +3 位作者 王树杰 徐孝辉 袁鹏 于鹏鹏 《海洋湖沼通报》 CSCD 北大核心 2020年第5期1-8,共8页
潮流能水轮机在实际运转时,水轮机叶片性能会受到其支撑结构的影响。以带变桨距系统的50kW水平轴潮流能水轮机为研究对象,选择采用CFD方法,使用Code_Saturne软件对处于不同工况下的实尺度潮流能水轮机进行数值仿真,研究支撑结构对潮流... 潮流能水轮机在实际运转时,水轮机叶片性能会受到其支撑结构的影响。以带变桨距系统的50kW水平轴潮流能水轮机为研究对象,选择采用CFD方法,使用Code_Saturne软件对处于不同工况下的实尺度潮流能水轮机进行数值仿真,研究支撑结构对潮流能水轮机性能的影响规律。研究结果表明,当50kW潮流能水轮机工作于1.5m/s流速时,正向迎流工况下支撑结构对水轮机的影响较小,但反向迎流工况下支撑结构对水轮机的影响非常剧烈,单一叶片划过支撑结构尾流区域时轴向力衰减约22.4%,升力衰减约91%,转子整体轴向力波动约为7%,整体获能效果衰减约31%。本文同时为实尺度潮流能水轮机的性能预测提供一种研究方法。 展开更多
关键词 潮流能水轮机 支撑结构 实尺度 反向迎流 Code_saturne 数值仿真
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南昌市城区883名儿童血铅水平及影响因素调查 被引量:13
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作者 游志华 胡向耘 +5 位作者 晁明霞 周芸 秦俊 周小军 熊丽萍 周和寅 《微量元素与健康研究》 CAS 2001年第2期53-55,共3页
目的 :了解南昌市城区 2~ 8岁儿童血铅水平现状及影响因素。方法 :采用严格质量控制的流行病学研究方法 ,于 2 0 0 0年 4~ 6月对南昌市城区 883名 2~ 8岁儿童进行血铅水平测定 ,并对其个人健康状况、家庭环境及生活卫生习惯等相关因... 目的 :了解南昌市城区 2~ 8岁儿童血铅水平现状及影响因素。方法 :采用严格质量控制的流行病学研究方法 ,于 2 0 0 0年 4~ 6月对南昌市城区 883名 2~ 8岁儿童进行血铅水平测定 ,并对其个人健康状况、家庭环境及生活卫生习惯等相关因素进行问卷调查。结果 :883名儿童血铅水平均数为 84.2 4 μg/L( 1 μg/L=0 .0 0 4 83μmol/L) ,其中高于目前国际公认的儿童铅中毒诊断标准 1 0 0μg/L的比例是 32 .84%。血铅值在 1 0 0~ 1 49μg/L ( - A级 ) 2 64例 ,占30 % ;1 50~ 1 99μg/L( - B级 ) 2 6例 ,占 3% ;>2 0 0μg/L( 级 ) 0例。各年龄段儿童血铅值及铅中毒率无明显差异。家庭住址、乘坐汽车及摩托车的频数、父母职业、不良生活卫生习惯、住房条件及父母吸烟量是影响儿童血铅值的主要危险因素。结论 :南昌市城区儿童血铅水平及铅中毒率已较高 ,应引起家长及有关方面的关注。 展开更多
关键词 儿童 铅中毒 南昌市 血铅水平测定 幼儿保健卫生
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《授时历》五星推步的精度研究 被引量:9
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作者 李勇 《天文学报》 CSCD 北大核心 2011年第1期43-53,共11页
着重考察了《授时历》的步五星术,考校、复原了其推步方法.(1)推步了1299年木星历,并与已有研究进行比对,从而确认恢复方法的正确性.(2)得出《授时历》在1280~1650年间推步五星黄经的精度,木星、火星、土星、金星和水星的误差的绝对值... 着重考察了《授时历》的步五星术,考校、复原了其推步方法.(1)推步了1299年木星历,并与已有研究进行比对,从而确认恢复方法的正确性.(2)得出《授时历》在1280~1650年间推步五星黄经的精度,木星、火星、土星、金星和水星的误差的绝对值平均分别为0.49°、1.91°、0.70°、2.82°和5.01°,木星、土星的精度较高.(3)指出将现代天文方法获取的《授时历》五星参数(周率、历率、度率、合应及历应)精确值代入《授时历》推步模型,木星、土星的推步精度并未提高,误差分别为1.83°和1.21°,而水星、金星和火星的误差却大幅加大,结果分别为30.04°、54.86°和10.82°.说明某些重要参数的修正并不能改善推步结果. 展开更多
关键词 天文学史和哲学 历书 行星与卫星 个别 木星 火星 土星 金星 水星
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Multiverse/Hyperverse Models: (4 + 1)-Dimensional Landscape (Black Saturns, Bousso-Hawking Nucleation, Gogberashvili Multiverses, Schwarzschild-De Sitter Nurseries) and a (3 + 1)-Dimensional Model for Dark Energy
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作者 Igor Yu. Potemine Werner Krause 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1866-1877,共12页
We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If ... We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If gis the gravitational constant of a shell Sand εits thickness, then G~εg. The physical universe is supposed to be one of those thin shells inside the local bouquet called Local Multiverse. Other remarkable objects of the Hyperverse are supposed to be black holes, black lenses, black rings and (generalized) Black Saturns. In addition, Schwarzschild-de Sitter multiversal nurseries can be hidden inside those Black Saturns, leading to their Bousso-Hawking nucleation. It also suggests that black holes in our physical universe might harbor embedded (2 + 1)-dimensional multiverses. This is compatible with outstanding ideas and results of Bekenstein, Hawking-Vaz and Corda about “black holes as atoms” and the condensation of matter on “apparent horizons”. It allows us to formulate conjecture 12.1 about the origin of the Local Multiverse. As an alternative model, we examine spacetime warping of our universe by external universes. It gives data for the accelerated expansion and the cosmological constant Λ, which are in agreement with observation, thus opening a possibility for verification of the multiverse model. 展开更多
关键词 5-Dimensional Gravity Black Hole Black saturn Cosmological Constant Dark Energy MULTIVERSE Spacetime Warping Thin Shell
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乡镇企业铅污染导致儿童铅中毒的流行病学调查 被引量:5
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作者 李恒新 宋雅丽 +4 位作者 李红光 袁永新 徐清 刘恩绪 李金松 《中华预防医学杂志》 CAS CSCD 北大核心 2008年第3期156-159,共4页
目的了解铅污染事件发生村及周边单位儿童铅中毒、血铅超标状况与范围,分析血铅水平与年龄、性别关系及对儿童健康的影响,为进一步采取预防控制措施提供依据。方法对污染源及周边环境进行调查;对事件发生村及周边单位14岁以下的221... 目的了解铅污染事件发生村及周边单位儿童铅中毒、血铅超标状况与范围,分析血铅水平与年龄、性别关系及对儿童健康的影响,为进一步采取预防控制措施提供依据。方法对污染源及周边环境进行调查;对事件发生村及周边单位14岁以下的221例儿童采集静脉血样、用原子吸收光谱法测定血铅;通过问卷调查了解儿童主要铅中毒症状,用SPSS13.0进行统计学分析。结果儿童高铅血症检出率66.06%(146/221),铅中毒检出率32.13%(71/221)。该村一、二、三组及玉石厂儿童血铅水平分别为(161.20±32.94)、(176.60±43.62)、(258.00±106.08)和(238.01±55.20)μg/L,经Kruskal-Wallis秩和检验差异有统计学意义(X^2=51.84,df=3,P〈0.01);三组和玉石厂组显著高于一组和二组。未发现儿童年龄与血铅水平存在相关性(r=0.10,P=0.13),但男女性别间血铅水平差异有统计学意义(t’=3.83,P〈0.01)。随血铅水平升高,儿童铅中毒主要症状发生率明显上升。调查表明污染源为一粗铅冶炼厂。结论在粗铅冶炼厂周边居住的儿童血铅水平普遍增高,部分发生铅中毒,铅中毒对儿童健康造成了影响。 展开更多
关键词 铅中毒 神经系统 儿童 环境污染 流行病学研究
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A prediction method for ground-based stellar occultations by ellipsoidal solar system bodies and its application 被引量:3
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作者 Ye Yuan Yan-Ning Fu Zhuo Cheng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第5期65-78,共14页
A new programmable prediction method is developed to refine the occultation band by taking into consideration the triaxiality of an occulting body, as well as two more factors, namely, the barycenter offset of an occu... A new programmable prediction method is developed to refine the occultation band by taking into consideration the triaxiality of an occulting body, as well as two more factors, namely, the barycenter offset of an occulting planet from the relevant planetary satellite system and the gravitational deflection of light rays due to an occulting planet. Although these factors can be neglected in most cases, it is shown that there are cases when these factors can cause a variation ranging from several tens to thousands of kilometers in the boundaries of occultation bands. Knowledge of analytic geometry simplifies the process of derivation and computation. This method is applied to long-term predictions of Jovian and Saturnian events. 展开更多
关键词 shadow stellar saturn Jupiter uncertainty programmable planet offset derivation refine
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五种营养素与铅中毒的相关性 被引量:4
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作者 成军 高丰 潘耀谦 《动物医学进展》 CSCD 2004年第1期65-66,共2页
铅中毒是动物较为常见的一种重金属中毒病。它以流涎、腹泻、腹痛等胃肠炎症状 ,兴奋狂燥、肌肉震颤、痉挛麻痹等神经症状以及铁失利用性贫血为其临床特征。研究表明 ,许多营养素能与铅相互作用 ,影响铅在体内的吸收及在组织、细胞内的... 铅中毒是动物较为常见的一种重金属中毒病。它以流涎、腹泻、腹痛等胃肠炎症状 ,兴奋狂燥、肌肉震颤、痉挛麻痹等神经症状以及铁失利用性贫血为其临床特征。研究表明 ,许多营养素能与铅相互作用 ,影响铅在体内的吸收及在组织、细胞内的分布与存积 ;反之 ,铅也会影响这些营养成分在体内的吸收和代谢。现就铁、钙。 展开更多
关键词 营养素 铅中毒 相关性 动物 重金属中毒病 缺铁性贫血 血红素
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土星系探测任务进展与展望
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作者 杜洋 张祎 +4 位作者 段晓闻 于淼 耿志卿 刘彤杰 牛俊坡 《上海航天(中英文)》 CSCD 2024年第5期69-78,共10页
《2021中国的航天》白皮书表示中国行星探测工程将实施小行星探测、火星采样返回、木星系探测等任务,对于更为远期的行星探测任务尚未有明确规划。土星是太阳系第二大行星,拥有美丽的星环和众多天然卫星,其中土卫二可能存在冰下海洋、... 《2021中国的航天》白皮书表示中国行星探测工程将实施小行星探测、火星采样返回、木星系探测等任务,对于更为远期的行星探测任务尚未有明确规划。土星是太阳系第二大行星,拥有美丽的星环和众多天然卫星,其中土卫二可能存在冰下海洋、土卫六是太阳系第二大天然卫星且是唯一一个拥有浓密大气的卫星,均具有极大的科学研究价值。本文对国外土星探测任务的发展状况进行了调研分析,包括已实施的先驱者11号、旅行者1号、旅行者2号、卡西尼-惠更斯号,以及后续的土卫二轨道-着陆器、土卫二多次飞越探测等。对这些任务的特点及实施土星系探测面临的关键难点进行了归纳总结。最后,提出了土星系探测的总体任务设想,进行了任务分析与初步设计,可作为中国后续行星探测任务规划的参考。 展开更多
关键词 土星 土星系 行星探测 深空探测
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逃离土星:格吕克作品中的忧郁书写及转向
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作者 郑春晓 《外国文学》 CSSCI 北大核心 2024年第3期157-167,共11页
2020年诺贝尔文学奖获得者露易丝·格吕克的作品向来以阴郁、沉静作为独特的风格戳记,其诗歌生产和运作的动力图式与“忧郁的土星”享有高度的通约性。在前期的写作过程中,她将个人经验中的抑郁症和厌食症作为诗歌的意义生成器,将... 2020年诺贝尔文学奖获得者露易丝·格吕克的作品向来以阴郁、沉静作为独特的风格戳记,其诗歌生产和运作的动力图式与“忧郁的土星”享有高度的通约性。在前期的写作过程中,她将个人经验中的抑郁症和厌食症作为诗歌的意义生成器,将对上帝的质疑和审视进行深度编码,忧郁似乎在格吕克的作品纹理和个性肌质中占有了绝对的统摄地位。然而在近期的作品中,格吕克放弃了之前对于忧郁的植入策略,反而更加强调日常生活所赋予和传达给人类的欢欣和快乐。格吕克作品中的土星气质逐渐湮没在积极意义的产生机制中,这不仅是格吕克写作风格的一大转折点,更是晚年的作者试图拯救自我于痛苦的渊薮中所做出的不懈努力。 展开更多
关键词 格吕克 忧郁 土星 转向
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Energy Gap in Saturn’s Rings
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作者 Andrey Yu Pospelov Vladimir V. Tchernyi 《Journal of Modern Physics》 2019年第4期477-485,共9页
In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the p... In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the planet’s rotation axis;3) “ring rain” of the submicron particles;4) the deviation in the qualitative composition of the “rain” from the composition of the rings;5) “dirt” concentrated in the ring gaps;6) “plateaus” in Saturn’s C ring;7) age of the rings;8) roll-off in the spectrum of Saturn’s rings, and 9) “propellers” in Saturn’s A ring. Interpretation of Cassini’s observations of spectral roll-off in Saturn’s rings in the wavelength range from 100 micrometers to 0.5 mm is given. It was concluded that the substance of the rings could be in the superconducting state. An explanation of the Cassini spectral data is given using the hypothesis of the existence of a superconducting energy gap in the substance of rings. 展开更多
关键词 saturn RINGS CASSINI CIRS Interpretation Super-Diamagnetic Model Superconducting Energy Gap Ring RAIN PLATEAUS and PROPELLERS in saturn’s RINGS
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Quantum Locking and the Meissner Effect Lead to the Origin and Stability of the Saturn Rings System
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作者 Vladimir V. Tchernyi (Cherny) Andrew Yu. Pospelov 《International Journal of Astronomy and Astrophysics》 2018年第1期104-120,共17页
It is demonstrated how superconducting iced particles of the protoplanetary cloud of Saturn are coming to magnetic equator plane and create the stable enough rings disk. There are two steps. First, after appearance of... It is demonstrated how superconducting iced particles of the protoplanetary cloud of Saturn are coming to magnetic equator plane and create the stable enough rings disk. There are two steps. First, after appearance of the Saturn magnetic field due to Meissner phenomenon, all particles orbits are moving to the magnetic equator plane. Finally they become distributed as rings and gaps like iron particles around magnet on laboratory table. And they are separated from each other by the magnetic field expelled from them. It takes up to few tens of thousands years with ten meters rings disk thickness. Second, because of quantum locking all particles become to be locked within magnetic well at the magnetic equator plane due to Abrikosov vortex for superconductor. Finally each particle is locked within three-dimensional magnetic well. It works even when particles have small fraction of superconductor. During the rings evolution some contribution to the disk also could come from the collision-generated debris of the current moon, coming meteorites and from the geysers like it happened due to magnetic coupling of Saturn and Enceladus. The rings are relict of the early days of the magnetic field of Saturn system. 展开更多
关键词 ORIGIN of saturn RINGS Age of saturn RINGS SUPERCONDUCTIVITY of saturn RINGS QUANTUM LOCKING of saturn RINGS Space SUPERCONDUCTIVITY QUANTUM Phenomena in Space
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About Role of Electromagnetism to the Saturn Rings Origin<br/>—To the Unified Theory of the Planetary Rings Origin
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作者 Vladimir V. Tchernyi 《International Journal of Astronomy and Astrophysics》 2013年第4期412-420,共9页
Experimental data observation of the Saturn rings points to the conjecture that the particles constituting the rings may be superconductive. The main argument for this based on the fact that Saturn has a magnetic fiel... Experimental data observation of the Saturn rings points to the conjecture that the particles constituting the rings may be superconductive. The main argument for this based on the fact that Saturn has a magnetic field and the temperature in its vicinity is low enough. Electromagnetic modeling shows the rings system emerges some time after appearance of the planetary magnetic field. Rings can be a result of the interaction of the superconducting carbon doped ice particles of the protoplanetary cloud with the nonuniform magnetic field. At the beginning all Keplerian orbits of the particles are located within protoplanetary cloud. After appearance of the magnetic field of Saturn, all iced particles demonstrate superconductivity and their orbits start to move to the magnetic equator plane where there is a minimum of magnetic energy. And then particles redistributed like iron particles nearby magnet on laboratory table forming system of rings and gaps. But rings particles are not stuck together because of Meissner phenomenon. The gravitational resonances and other interactions also play an important role and they help bring the order to the system of rings and gaps. It becomes to be clear why the rings appear only for the planets with magnetic field outside the asteroid belt such as Jupiter, Saturn, Uranus and Neptune. Inside the asteroid belt Sun’s heat is destroying superconductivity. Scenario of the rings creation for all planets could be the same. So we are coming to the unified theory of the rings origin. The presented model allows enriching the well-known theories that treat gravitational, mechanical, gas-plasma, dusty plasma and magnetohydrodynamic interactions in a consistent way. 展开更多
关键词 saturn System saturn RINGS ORIGIN saturn RINGS Electromagnetism saturn RINGS SUPERCONDUCTIVITY ORIGIN of PLANETARY RINGS SPACE Electromagnetism SPACE SUPERCONDUCTIVITY
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土星及其卫星的新面貌 被引量:1
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作者 胡中为 《自然杂志》 北大核心 2006年第1期22-27,共6页
土星有美丽环系和50颗卫星环绕,特别是土卫六有浓厚大气和类似于地球早期生命存在的环境。1997年发射的卡西尼惠更斯飞船,经7年的长途旅程,于去年进入环绕土星的运行,探测神秘的土星及其卫星系统,尤其是土卫六。从飞船投放的惠更斯探测... 土星有美丽环系和50颗卫星环绕,特别是土卫六有浓厚大气和类似于地球早期生命存在的环境。1997年发射的卡西尼惠更斯飞船,经7年的长途旅程,于去年进入环绕土星的运行,探测神秘的土星及其卫星系统,尤其是土卫六。从飞船投放的惠更斯探测器于2005年1月14日成功地降落到土卫六表面,而卡西尼轨道器将环绕土星进行4年探测。飞船已发送回来的新颖图像和资料令科学家和公众惊喜,新发现纷至沓来。这次太空探测壮举成为新的里程碑。 展开更多
关键词 土星 土星环系 土卫六 卡西尼-惠更斯飞船
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Observations of loading-unloading process at Saturn's distant magnetotail 被引量:1
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作者 ZhongHua Yao 《Earth and Planetary Physics》 2017年第1期53-57,共5页
Using in-situ measurements from the Cassini spacecraft in 2013, we report an Earth substorm-like loading-unloading process at Saturn's distant magnetotail. We found that the loading process is featured with two di... Using in-situ measurements from the Cassini spacecraft in 2013, we report an Earth substorm-like loading-unloading process at Saturn's distant magnetotail. We found that the loading process is featured with two distinct processes: a rapid loading process that was likely driven by an internal source and a slow loading process that was likely driven by solar wind. Each of the two loading processes could also individually lead to an unloading process. The rapid internal loading process lasts for ~ 1-2 hours; the solar wind driven loading process lasts for ~ 3-18 hours and the following unloading process lasts for ~1-3 hours. In this letter, we suggest three possible loadingunloading circulations, which are fundamental in understanding the role of solar wind in driving giant planetary magnetospheric dynamics. 展开更多
关键词 saturn magnetosphere loading-unloading process magnetic reconnection DIPOLARIZATION
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Superconductivity of Saturn Rings: Quantum Locking, Rings Disc Thickness and Its Time Creation
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作者 Vladimir V. Tchernyi Andrew Yu Pospelov 《Journal of Modern Physics》 2018年第3期419-432,共14页
The article demonstrates how rings disc of Saturn was created after appearance of the planetary magnetic field from superconducting iced particles of the protoplanetary cloud moving around planet by chaotic orbits. It... The article demonstrates how rings disc of Saturn was created after appearance of the planetary magnetic field from superconducting iced particles of the protoplanetary cloud moving around planet by chaotic orbits. It is based on the fact that Saturn has magnetic field and the temperature of its vicinity is low enough to have superconductivity. Electromagnetic simulation estimates time of rings disc formation with the thickness about few meters from a few thousand years up to few tens of thousands of years. A rings disk has a stable structure located within magnetic equator of Saturn due to quantum locking of the particles by planetary magnetic field. Also may happened contribution to the rings disc from the debris of the moons migrated inward towards Saturn and particles of the frozen water coming from the geyser of the geologically active satellite (as Enceladus contributed to the E-ring). Suggested mechanism of the rings formation works even in case where only a small fraction of the particles poses superconductivity. Presented electromagnetic modeling of the role of superconducting iced particles of the rings disc origin, dynamics and evolution allow us to enrich the classical theories based on gravitational, mechanical, magnetohydrodynamic and plasma interactions. 展开更多
关键词 ORIGIN of saturn RINGS ORIGIN of PLANETARY RINGS SUPERCONDUCTIVITY of the PLANETARY RINGS
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基于静态分析的XSM正确性验证
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作者 邓程 丁丽萍 +1 位作者 贺也平 韩伟 《计算机应用与软件》 CSCD 北大核心 2012年第9期1-5,22,共6页
XSM(Xen Security Module)是虚拟机Xen的安全模型框架,对系统的安全性具有决定性的作用。目前,对类似的强制访问框架的正确性验证研究主要集中于对钩子函数放置的验证。现有检测方法通常路径覆盖不够完整,或者有较高的误报率。对XSM框... XSM(Xen Security Module)是虚拟机Xen的安全模型框架,对系统的安全性具有决定性的作用。目前,对类似的强制访问框架的正确性验证研究主要集中于对钩子函数放置的验证。现有检测方法通常路径覆盖不够完整,或者有较高的误报率。对XSM框架的正确性验证问题进行分析,提出一种过程间流敏感、过程内路径敏感的,适用于XSM框架的静态分析方法。该方法通过扩展静态分析工具Saturn,实现了对XSM框架的钩子函数设置的正确性和完备性的验证。经实验验证,该方法具有完全的路径覆盖性,并且具有较高的精确度。 展开更多
关键词 静态分析 正确性验证 XSM 钩子函数 saturn
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Oblateness Effect of Saturn on Halo Orbits of L1 and L2 in Saturn-Satellites Restricted Three-Body Problem
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作者 Nishanth Pushparaj Ram Krishan Sharma 《International Journal of Astronomy and Astrophysics》 2016年第4期347-377,共31页
The Circular Restricted Three-Body Problem (CRTBP) with more massive primary as an oblate spheroid with its equatorial plane coincident with the plane of motion of the primaries is considered to generate the halo orbi... The Circular Restricted Three-Body Problem (CRTBP) with more massive primary as an oblate spheroid with its equatorial plane coincident with the plane of motion of the primaries is considered to generate the halo orbits around L1 and L2 for the seven satellites (Mimas, Enceladus, Tethys, Dione, Rhea, Titan and Iapetus) of Saturn in the frame work of CRTBP. It is found that the oblateness effect of Saturn on the halo orbits of the satellites closer to Saturn has significant effect compared to the satellites away from it. The halo orbits L1 and L2 are found to move towards Saturn with oblateness. 展开更多
关键词 Circular Restricted Three-Body Problem Lagrangian Points Halo Orbits OBLATENESS saturn
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Space Magnetism and Superconductivity: Diamagnetic Expulsion, Meissner Effect, Magnetic Pressure and Quantum Trapping Lead to the Origin and Stability of the Saturn Rings
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作者 Vladimir V. Tchernyi (Cherny) Andrey Yu. Pospelov Sergey V. Kapranov 《Journal of Applied Mathematics and Physics》 2019年第8期1625-1636,共12页
Existence of the magnetic field of Saturn and the temperature around 70 - 100 K nearby of it bring us to the idea of diamagnetism and superconductivity of the rings particles. The rings could emerge from the icy parti... Existence of the magnetic field of Saturn and the temperature around 70 - 100 K nearby of it bring us to the idea of diamagnetism and superconductivity of the rings particles. The rings could emerge from the icy particles moving on chaotic orbits around Saturn within protoplanetary cloud. After appearance of the magnetic field of Saturn all chaotic orbits of icy particles start to shift to the magnetic equator plane, where there is a minimum of the particles magnetic energy, due to diamagnetic force of expulsion like Meissner phenomenon. Each particle comes to the stable position preventing its own horizontal and vertical shift. Particles are locked within three-dimensional magnetic well due to Abrikosov quantum vortex phenomenon for superconductor. This mechanism is valid and it works even particles have a small fraction of superconductor. Final picture is similar to the picture of iron particles forms the same shape around a magnet on laboratory table. Any other phenomena like gravity resonances, dusty plasma and others may bring some peculiarities to the final picture of the rings. It follows that magnetic field of Saturn and low temperature around of it are the main reason for the rings origin and the rings is product of the early time of the magnetic field of Saturn appearance. Additional matter to the rings also may come from the frozen water particles generated from the Saturn sputniks geysers due to magnetic coupling between planet and satellites. The data of Cassini mission to Saturn rings are conforming suggested theory of their origin and existence. 展开更多
关键词 saturn Rings ORIGIN SPACE MAGNETISM SPACE DIAMAGNETISM SPACE SUPERCONDUCTIVITY SPACE Ice
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Gravitational transformation of gaseous clouds: The formation of spiral galaxies and disk planets
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作者 Andrei Pavlov 《Natural Science》 2014年第4期151-170,共20页
Gravitation is one of the central forces playing an important role in formation of natural systems like galaxies and planets. Gravitational forces between particles of a gaseous cloud transform the cloud into spherica... Gravitation is one of the central forces playing an important role in formation of natural systems like galaxies and planets. Gravitational forces between particles of a gaseous cloud transform the cloud into spherical shells and disks of higher density during gravitational contraction. The density can reach that of a solid body. The theoretical model was tested to model the formation of a spiral galaxy and Saturn. The formations of a spiral galaxy and Saturn and its disk are simulated using a novel N-body self-gravitational model. It is demonstrated that the formation of the spirals of the galaxy and disk of the planet is the result of gravitational contraction of a slowly rotated particle cloud that has a shape of slightly deformed sphere for Saturn and ellipsoid for the spiral galaxy. For Saturn, the sphere was flattened by a coefficient of 0.8 along the axis of rotation. During the gravitational contraction, the major part of the cloud transformed into a planet and a minor part transformed into a disk. The thin structured disk is a result of the electromagnetic interaction in which the magnetic forces acting on charged particles of the cloud originate from the core of the planet. 展开更多
关键词 GRAVITATION Planets saturn’s Rings Computer Simulation Planet’s Interior Structure Formation of GALAXIES Spiral GALAXIES N-BODY Simulations
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Saturn's gravitational field induced by its equatorially antisymmetric zonal winds
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作者 Dali Kong Keke Zhang +1 位作者 Gerald Schubert John D.Anderson 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第5期29-36,共8页
The cloud-level zonal winds of Saturn are marked by a substantial equatorially antisymmetric component with a speed of about 50 m s^-1 which, if they are sufficiently deep, can produce measurable odd zonal gravitation... The cloud-level zonal winds of Saturn are marked by a substantial equatorially antisymmetric component with a speed of about 50 m s^-1 which, if they are sufficiently deep, can produce measurable odd zonal gravitational coefficients △J2 k+1, k = 1, 2, 3, 4. This study, based on solutions of the thermal-gravitational wind equation, provides a theoretical basis for interpreting the odd gravitational coefficients of Saturn in terms of its equatorially antisymmetric zonal flow. We adopt a Saturnian model comprising an ice-rock core, a metallic dynamo region and an outer molecular envelope. We use an equatorially antisymmetric zonal flow that is parameterized, confined in the molecular envelope and satisfies the solvability condition required for the thermal-gravitational wind equation. The structure and amplitude of the zonal flow at the cloud level are chosen to be consistent with observations of Saturn.We calculate the odd zonal gravitational coefficients △J2k+1, k = 1, 2, 3, 4 by regarding the depth of the equatorially antisymmetric winds as a parameter. It is found that △J3 is-4.197 × 10^-8 if the zonal winds extend about 13 000 km downward from the cloud tops while it is-0.765 × 10^-8 if the depth is about 4000 km. The depth/profile of the equatorially antisymmetric zonal winds can eventually be estimated when the high-precision measurements of the Cassini Grand Finale become available. 展开更多
关键词 gravitation - planets and satellites individual saturn - planets and satellites INTERIORS
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